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Type 4 engine forensics
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furgo
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PostPosted: Thu Mar 01, 2018 8:35 am    Post subject: Type 4 engine forensics Reply with quote

As mentioned in another thread, I got a cheap Type 4 CU-code engine. I simply wanted to understand how it's put together before I tackle the rebuild of the engine on my bus at some point in the future.

I can then take it apart in my own time, with a functional engine on the bus, and without the risk of breaking anything. Forums and Bentley are a great help, but this is already giving me better first hand understanding about which things I can do myself, and which things I'd have to send the engine to a shop for. I've been also fixing a few things here and there.

First thing I did was a rough cleanup of all grease and cruft accumulated over the years. At this point, and until I figure out which parts can be reused (if any), I don't want to invest much in this engine, so you won't see any sandblasted or shiny parts. For now I cleaned it up enough so that I could assess its current status.

I can check some of the specs with Bentley (at least the ones I've got the tools for), but mostly, I've been looking at visual wear/damage at this point.

I thought I'd post some pictures in case they can be of interest to someone. Some questions cropped up as well

Camshaft

Image may have been reduced in size. Click image to view fullscreen.

Image may have been reduced in size. Click image to view fullscreen.


I'm not an expert, but I think this camshaft screams for replacement. The same wear pattern appears on all four lobes.

I'm curious, though...

• What noticeable effect would such a cam cause while driving?

Hydraulic lifters

Image may have been reduced in size. Click image to view fullscreen.


All lifter pairs show the same wear pattern as the two on the picture: fairly flat exhaust lifters, concave intake lifters.

• Is this uneven wear on intake vs. exhaust normal or were the lifters badly adjusted?
• Is the regular practice to fix (flatten) them or replace them altogether?
• Two of the lifters were stuck enough that I could not extract them with a magnet alone. I could stick my hand through the cylinder bore and barely push it from the other side with some finger contorsionism and magnet pull. Is the fact that they were stuck indicative of an issue?

Pistons

First of all, the engine did not turn a full revolution when I first got it. It didn't turn completely after removing the pushrods and lifters either. It only did after the cylinder heads were removed.

I could be wrong, but looking at the "before" picture, I would say it was the accumulation of crud between one of the cylinder tops and its combustion chamber that didn't let it reach the top. That's what it looked like before:

Image may have been reduced in size. Click image to view fullscreen.

Image may have been reduced in size. Click image to view fullscreen.


Notice the white crusty stuff. I don't know what it is, but it's proving quite hard to remove.

Here's what the pistons look like after the first cleaning iteration. As you can see, there are still residues of the white crust.

Image may have been reduced in size. Click image to view fullscreen.

Image may have been reduced in size. Click image to view fullscreen.

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Image may have been reduced in size. Click image to view fullscreen.


Pistons 3 and 4 look not too bad, other than some mild pitting on #4. The middle ring on piston #3 was stuck compressed, held by crud.

Pistons 1 and 2 look pretty chewed, with the matching damage on their corresponding combustion chambers.

• Tips on what the white residue is and how to best remove it (other than slowly scraping it off)?
• What could have caused the damage on pistons 1 and 2? I could not see any metal bits while draining the oil/sludge.

Cylinder heads

Here's what the combustion chambers looked like before initial cleanup: I'd say that at least on cylinders #2, #3 and #4 there was some sort of leak. Some of the sealing rings in the combustion chambers were no longer round (were this the rings that VW mentioned to no longer use at some point?)

Image may have been reduced in size. Click image to view fullscreen.
(The mislabeled "3" should be a "4", sorry)
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I have not yet taken the valves apart, but at least I could observe no visible cracks on the combustion chambers. I noticed the white crust again on the exhaust valves.

Image may have been reduced in size. Click image to view fullscreen.

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The boss for the screw that holds the deflector plate is split, with parts of the original screw seemingly still in. Short of welding, which would be overkill for the current plans for the engine, I'm thinking I could perhaps drill and tap a deeper hole for a longer screw. The two split bits might come back a bit closer with some coercion.

Image may have been reduced in size. Click image to view fullscreen.


Two of the studs on the exhaust ports are broken. Presumably while removing the heat exchangers the nuts could not be undone and part of the stud eventually broke. I'll see if I can remove the studs, but I'm fearing they will be well stuck and might need to be cut off, drilled and replaced with a thread insert.

Image may have been reduced in size. Click image to view fullscreen.


Oh, and all the screws that hold the cylinder tin against the head were broken too.

Cylinder studs

Removing the cylinder heads proved to be a bit of a challenge. The nuts that held them in place on the cylinder studs were badly rusted. I could undo most of them with a combination of heat and hammer taps, but four of them wouldn't budge.

In fact, the studs themselves got undone instead. I ended up splitting the nuts and getting new ones. I noticed two things on the studs:

Image may have been reduced in size. Click image to view fullscreen.

Image may have been reduced in size. Click image to view fullscreen.


• They are through holes to the inside of the case. Some of them were dry, but some of them were visibly oily. I wonder if sealant needs to be applied before putting them back in?
• The thread on one of the studs was visibly damaged. I'm not sure what could have caused it, as the aluminium case should be softer than the steel studs. I'm not sure whether I should just refit the stud as it is, or replace it and rethread the hole (which I'm not actually sure it's damaged).

Flywheel

Image may have been reduced in size. Click image to view fullscreen.


The flywheel has two broken teeth, and at least three more that are noticeably chipped.

• Can flywheels be repaired at all or is this one unusable and needs to be thrown away?

Other than all this, are there any other obvious spots that should be examined for wear and that I've missed?
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Wildthings
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PostPosted: Thu Mar 01, 2018 9:28 am    Post subject: Re: Type 4 engine forensics Reply with quote

Type 4 engines benefit from having their lifters replaced or at least reground every 80-100K miles. This prevents them for wearing severely concave and damaging the cam in the process. A concave lifter also has that much less lift than a flat or domed lifter thereby harming performance.

When a Type 4 engine sits for a long while it is common for some of the buildup on the head and pistons to flake off and fall downward. This will cause the piston to jam against the head so the engine can not be turned a complete revolution.

The cylinder with the whitish corrosion and rusty looking valves has had water in it.
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PostPosted: Thu Mar 01, 2018 9:35 am    Post subject: Re: Type 4 engine forensics Reply with quote

Wow!.....heavily abused. I have not seen a camshaft that bad in years. Disassemble the oil pump to show us what it looks like. I am suspecting pretty bad.

The white stuff....is corrosion from water damage. The cam is more heavily worn than normal because....from the looks of it....the previous owner never changed the oil and it was filthy. That causes wear.....and that wear also causes poor oil pressure.....which causes poor hydraulic lifter performance....and coupled with that probably the lifters were not even adjusted correctly. The dished lookiny lifter is heavily worn.

Next for the cam.....the heavily worn spots will be subject to faster corrosion damage which is evident from the severe pitting along the edges of the first cam lobe picture.

The rolled threads on that cylinder stud are bad news. You will need to ijstall an insert to fix those. Take a look ar my 1.8L buikd thread in the 411/412 forum.

I never remove cylinder studs until I split the case. In a rusty engine you have rust growth on the inside face of the stud. You need to first sand or file that away....then heat the stud at the case to about 400F.....treat with penetrating oil from goth sides, strike the stud to set up vibration....let sit for an hour or two.....then heat again and remove.

Two of your combustion chambers look like they swallowed small pieces of hardware at one time.

The cracked exhaust stud boss will need welding....and new everything. I think you can salvage the case....maybe the crank and timing gears and flywheel....the rest i would scrap. Looking at how much metal was circulating in the oil....do not re-use the oil cooler. Ray
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PostPosted: Thu Mar 01, 2018 10:14 am    Post subject: Re: Type 4 engine forensics Reply with quote

Thanks both for the replies. I really appreciate the knowledge sharing here.

Wildthings wrote:
When a Type 4 engine sits for a long while it is common for some of the buildup on the head and pistons to flake off and fall downward. This will cause the piston to jam against the head so the engine can not be turned a complete revolution.


I think that was exactly the case.

raygreenwood wrote:
Wow!.....heavily abused. I have not seen a camshaft that bad in years. Disassemble the oil pump to show us what it looks like. I am suspecting pretty bad.


Sure, will do. I just need to look up how to first, I'll see if I can find some time this evening.

raygreenwood wrote:
The white stuff....is corrosion from water damage.


I'm guessing aluminum corrosion from the heads, right? It just puzzled me a bit, as it seems to have stuck mostly on the exhaust valves and on the piston tops.

raygreenwood wrote:
I never remove cylinder studs until I split the case. In a rusty engine you have rust growth on the inside face of the stud. You need to first sand or file that away....then heat the stud at the case to about 400F.....treat with penetrating oil from both sides, strike the stud to set up vibration....let sit for an hour or two.....then heat again and remove.


I can follow that, but I'm not really sure if it applies to this particular stud: once the initial fastening torque was broken, the stud came out really easily, I wasn't forcing the thread. It was almost as if the thread had been damaged upon insertion. Also the damage appears to have been done from the outer side of the case.

Out of interest, is it custom practice to remove the studs at all when rebuilding an engine? And also, how do you control the applied heat to be 400F (the only way I can think of is with a temperature-regulated soldering iron)?

raygreenwood wrote:
The cracked exhaust stud boss will need welding


Ah, I think here we're talking about two different things, sorry if that wasn't clear on the first post:

• The cracked boss is for the small screw that holds the deflector plate. I don't see it as too critical if I can perhaps drill a deeper hole for a longer screw.
• There are two broken exhaust studs. If I can extract them, then good. If not, they might need to be drilled and a thread insert installed.

raygreenwood wrote:
I think you can salvage the case....maybe the crank and timing gears and flywheel....the rest i would scrap.


Yeah, although I was hoping I could also salvage pistons #3 and #4 after removing the white crust from #3. If not, also fine. This engine is already worth its value just for the experience gained so far.

Also flywheel... do you think that can be salvaged despite the two broken teeth?

raygreenwood wrote:
Looking at how much metal was circulating in the oil....do not re-use the oil cooler.


I had not thought of that. Would you mind elaborating on it? I'm guessing metal bits might be obstructing or otherwise might have damaged the oil passages?
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PostPosted: Thu Mar 01, 2018 10:52 am    Post subject: Re: Type 4 engine forensics Reply with quote

Ah....I missed the screw boss. Thinks tend to look odd on my phone.

On the cylijder stud.....if it came out that way with the inner threads rolled....and it came out easy....its damage from a previous owner.

Do you need to take them out?.....yes.

30 years ago when these engines were on their first rebuild....likely you would have no reason to remove them. Now....all cases....especially abused ones....should hsve them pulled.....and checked for sinking between case bores..... lean the studs up well and check for damage like you found. About 3 out of five cases or more need to have the cylinder seating surfaces machined flat.

Excessive wear of metal parts puts lots of metal and debris sediment into the oil cooler passages. Because if was likely run for eons on standard oil.....the particles do not stay suspended. They sediment into the oil cooler.

You can likely save the pistons if none of the ring lands are too worn, have corrosion damage and if the skirts are not excessigly scored and are not measuring to have heat cycling collapse.

If the cylinders have rust pits, scoring or marks that cannot be cleaned up with a LIGHT hone.....without oversizing them.....then the cylinders cannot be used with those pistons......BUT....if they are otherwise straight and round and no broken fins....they are good candidates to save to hone out to first oversize if you can find a piston set. Ray
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PostPosted: Thu Mar 01, 2018 11:05 am    Post subject: Re: Type 4 engine forensics Reply with quote

furgo wrote:

I can follow that, but I'm not really sure if it applies to this particular stud: once the initial fastening torque was broken, the stud came out really easily, I wasn't forcing the thread. It was almost as if the thread had been damaged upon insertion. Also the damage appears to have been done from the outer side of the case.


What probably happened is that the cylinders were twisted a bit and as the stud came out it scraped against the fins of the cylinder. This could either be recent damage or preexisting damage.

I would say the cam looks pretty normal for a high mileage Vanagon engine. Since the valves on these engines are self adjusting and the cooling system was a bit better many of these engines got over 300K miles (500K kilometers), keeping mechanics grubby hands away from an engine is about the best way to get them to last and the Vanagon Type 4 just lasted better than a Bay or Type 4 car for this reason. I would not be too worried that either the oil pump or oil cooler is that bad. Definitely inspect them well and replace if questionable. Be warned that the idler shaft can work its way out of the oil pump case and cause engine destruction. Pressing out the idler shaft, grinding it a bit shorter, pressing it back in and then doing an improved peen job to keep it in place is the answer.
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PostPosted: Thu Mar 01, 2018 12:44 pm    Post subject: Re: Type 4 engine forensics Reply with quote

Wildthings wrote:
furgo wrote:

I can follow that, but I'm not really sure if it applies to this particular stud: once the initial fastening torque was broken, the stud came out really easily, I wasn't forcing the thread. It was almost as if the thread had been damaged upon insertion. Also the damage appears to have been done from the outer side of the case.


What probably happened is that the cylinders were twisted a bit and as the stud came out it scraped against the fins of the cylinder. This could either be recent damage or preexisting damage.


That sounds plausible, particularly if someone was doing the work with the engine in. I don't see any scratch marks on the cylinder, though, but I'm hoping that that's the case, which would mean the thread on the engine case is still ok and no thread insert is needed.

Wildthings wrote:
I would say the cam looks pretty normal for a high mileage Vanagon engine. Since the valves on these engines are self adjusting and the cooling system was a bit better many of these engines got over 300K miles (500K kilometers), keeping mechanics grubby hands away from an engine is about the best way to get them to last and the Vanagon Type 4 just lasted better than a Bay or Type 4 car for this reason.


Ok Smile

Wildthings wrote:
I would not be too worried that either the oil pump or oil cooler is that bad. Definitely inspect them well and replace if questionable. Be warned that the idler shaft can work its way out of the oil pump case and cause engine destruction. Pressing out the idler shaft, grinding it a bit shorter, pressing it back in and then doing an improved peen job to keep it in place is the answer.


I'll inspect both in any case. I don't know yet how to examine the cooler, as I'm trying to pry out the oil pump first. I've read the removal procedure from Bentley, and I'm trying to find some small pry bars to pull the pump by its ears without damaging either case or ears. The pump seems to be well stuck.
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PostPosted: Thu Mar 01, 2018 1:06 pm    Post subject: Re: Type 4 engine forensics Reply with quote

furgo wrote:

Wildthings wrote:
I would say the cam looks pretty normal for a high mileage Vanagon engine. Since the valves on these engines are self adjusting and the cooling system was a bit better many of these engines got over 300K miles (500K kilometers), keeping mechanics grubby hands away from an engine is about the best way to get them to last and the Vanagon Type 4 just lasted better than a Bay or Type 4 car for this reason.


Ok Smile


I am not meaning that the cam is in good condition, just that the level of wear would be normal for a cam with several hundred thousand miles on it. If the engine were still installed and in otherwise suitable condition, I might just regrind the lifters and try to run with the existing cam, but with the engine out and partially disassembled it should get a new cam at this point.

With engines running solid lifters most will die for one reason or another before it gets as many miles on it as a hydraulic cam engine is apt to get.
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PostPosted: Thu Mar 01, 2018 1:48 pm    Post subject: Re: Type 4 engine forensics Reply with quote

Vanagon type 4's outlast a type 4 in a type 4 car?......never seen one yet that did.

Ray
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PostPosted: Thu Mar 01, 2018 3:46 pm    Post subject: Re: Type 4 engine forensics Reply with quote

raygreenwood wrote:
Vanagon type 4's outlast a type 4 in a type 4 car?......never seen one yet that did.

Ray


200-300K miles is fairly common for a Vanagon aircooled that was half way maintained, same for a late Bay with hydraulic lifters. Solids are fine assuming they get maintained regularly, but this is a big "if" that doesn't happen in real life. From what I remember the Type 4 car made about the fastest trip from the showroom floor to the wrecking yard of anything VW (and most other manufactures) produced in that era, I know that I stripped parts off of many.
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PostPosted: Thu Mar 01, 2018 4:40 pm    Post subject: Re: Type 4 engine forensics Reply with quote

Get the Wilson book about rebuilding vw engines. I highlighted all the type 4 items in my copy when I redid mine, it made it easier to read the pertaining items.

That's a right nasty engine you have there, but with clean up and measurements you can evaluate. Interested to see what the bearings have to say.

The white stuff baked on the valves, was there the same type of stuff on the plugs? Wondering if someone was dumping injector cleaner or or some magic FLAPS fluid in it to make it run better.
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PostPosted: Thu Mar 01, 2018 5:20 pm    Post subject: Re: Type 4 engine forensics Reply with quote

I second the idea that the stud damage was from it binding against something external on the way out. All it takes is a small rock stuck between 2 cylinder fins.

I have seen marking like is on your heads and pistons just from big chunks of carbon breaking loose while the engine is running. I see heavy carbon deposits on those cylinders that look like they have been shedding chunks.
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PostPosted: Thu Mar 01, 2018 5:32 pm    Post subject: Re: Type 4 engine forensics Reply with quote

If you find you need to drill out the exhaust studs, find yourself an old manifold you can cut one of the flanges off to use as a drilling guide. Cut off the studs near the head leaving a bit protruding to align your guide and then do the most perfect job you can center punching the studs and drill a bit down into each with a fairly small bit. Now install your drilling guide somehow and drill down through the guide keeping the bit centered in the opening.

Your flywheel is trash Crying or Very sad

For your cracked out hole in the head, drill deeper and use a longer bolt, assuming there is metal there to do this.
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PostPosted: Thu Mar 01, 2018 6:00 pm    Post subject: Re: Type 4 engine forensics Reply with quote

The white stuff on the valves and pistons looks like lead to me, it's been a long time since I've seen that in a car, but that engine also looks like it's sat a long time so maybe it's last meals were high in leaded gas? Or has it been run on 100LL Avgas?, that shit still leaves those deposits in aero engines today. The rest of the crud looks like rich mixture and oil consumption mixed with moisture and time sitting.

The tin screw hole should be repairable by drilling deeper and using a longer screw.

The exhaust studs might start moving after repeated heating to red with Oxy/acetelene followed by a PB Blaster bath and some hammering and visegrip twisting, if the stub starts getting too short (~1/4") weld a nut on with a MIG using a hot bead, that alone may make it see it your way.
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PostPosted: Thu Mar 01, 2018 7:52 pm    Post subject: Re: Type 4 engine forensics Reply with quote

As Mark said, the exhaust deposits look like leaded fuel to me too. I think until everything is apart, glass beaded (except case), checked for cracks and pitting, list of items that need to be machined it is hard to know what you have there. Certainly a project and there will be no cutting of corners with this engine if you want it to last a while after it is rebuilt.
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PostPosted: Thu Mar 01, 2018 8:53 pm    Post subject: Re: Type 4 engine forensics Reply with quote

Don't get too flustered over extracting the oil pump,
it will be better if you leave it in place & then back off the perimeter
nuts/bolts then go for the main case studs too, after that & heat gun use
you can have it with ears still intact! Some of those factory pumps fit TIGHT.
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PostPosted: Fri Mar 02, 2018 5:54 am    Post subject: Re: Type 4 engine forensics Reply with quote

my59 wrote:
Get the Wilson book about rebuilding vw engines. I highlighted all the type 4 items in my copy when I redid mine, it made it easier to read the pertaining items.


Good call. I do have it, and along with Bentley it has already helped a lot. I will use them to check the specs when I'm done with the cleanup, but the collective knowledge here in The Samba for an initial visual assessment is also being extremely useful.

my59 wrote:
Interested to see what the bearings have to say.


Sure, I'll post some pictures once I've split the case. It will be the first time I do this and might take me a while, though.

oprn wrote:
I second the idea that the stud damage was from it binding against something external on the way out. All it takes is a small rock stuck between 2 cylinder fins.


Yeah, the stud damage looks like it was on the way out.

oprn wrote:
I have seen marking like is on your heads and pistons just from big chunks of carbon breaking loose while the engine is running. I see heavy carbon deposits on those cylinders that look like they have been shedding chunks.


That's one bit that still has me puzzled, particularly having no previous experience on this. As mentioned, I could not find any chunks of metal when I drained the oil. Admittedly, the damage could have been done way before the engine was put to rest and the metal bits might have been extracted already. I don't have a feel for how strong carbon deposits would be to either cause such dents or just be squeezed away. I would have rather expected loose metal parts to dent the steel in the pistons.

Wildthings wrote:
If you find you need to drill out the exhaust studs, find yourself an old manifold you can cut one of the flanges off to use as a drilling guide. Cut off the studs near the head leaving a bit protruding to align your guide and then do the most perfect job you can center punching the studs and drill a bit down into each with a fairly small bit. Now install your drilling guide somehow and drill down through the guide keeping the bit centered in the opening.


Great suggestion, thanks. I'd rather not drill unless I have to, so I'll try busdaddy's suggestion to heat the remaining stud bits to glowing red and use some pliers to take them out.

Wildthings wrote:
Your flywheel is trash Crying or Very sad


I thought so, thanks for confirming. I had little hope that those could be restored, so be it.

Wildthings wrote:
For your cracked out hole in the head, drill deeper and use a longer bolt, assuming there is metal there to do this.


Yeah, that was my plan. There seems to be enough metal deepwise.

busdaddy wrote:
The white stuff on the valves and pistons looks like lead to me, it's been a long time since I've seen that in a car, but that engine also looks like it's sat a long time so maybe it's last meals were high in leaded gas? Or has it been run on 100LL Avgas?, that shit still leaves those deposits in aero engines today. The rest of the crud looks like rich mixture and oil consumption mixed with moisture and time sitting.


Ok, I might try to scrape it out or see how much it'd cost to glass bead the heads. Unless there are no cracks, at least the head without the dents might be salvageable. Not sure if something can be done to the other one, though.

busdaddy wrote:
The exhaust studs might start moving after repeated heating to red with Oxy/acetelene followed by a PB Blaster bath and some hammering and visegrip twisting, if the stub starts getting too short (~1/4") weld a nut on with a MIG using a hot bead, that alone may make it see it your way.


I'll give it a go, thanks.

SGKent wrote:
As Mark said, the exhaust deposits look like leaded fuel to me too. I think until everything is apart, glass beaded (except case), checked for cracks and pitting, list of items that need to be machined it is hard to know what you have there. Certainly a project and there will be no cutting of corners with this engine if you want it to last a while after it is rebuilt.


Thanks. Out of interest, why should the case not be glass beaded?

timvw7476 wrote:
Don't get too flustered over extracting the oil pump,
it will be better if you leave it in place & then back off the perimeter
nuts/bolts then go for the main case studs too, after that & heat gun use
you can have it with ears still intact! Some of those factory pumps fit TIGHT.


I think mine is fairly tight. Unless I can get it out on the next go, I'm considering leaving the extraction for when I split the case.
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PostPosted: Fri Mar 02, 2018 7:45 am    Post subject: Re: Type 4 engine forensics Reply with quote

Shocked you can never be sure ALL if the glass beads will be cleaned out of the oil galleys- and some can be embedded in the case for a time release effect. either way disaster is right round the corner.
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raygreenwood
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Location: Oklahoma City
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PostPosted: Fri Mar 02, 2018 9:51 am    Post subject: Re: Type 4 engine forensics Reply with quote

In second look.....a chunk of the abrasion damage done to the quench areas of the combustion chambers also looks like scarring happens when one uses a cheap bench top valve remover tool without protective pads.

Look at the combustion chamber for cylinder # in your pictures. See you some of the aluminum on the sharp edge of the flat quench area seems to be mashed over into the chamber area?.....that does not look like it was caused by carbon or debris.

Also.....While its possible that the white residue has some lead residue....is most probably not. That is also the exact color and grain texture of what is called "white ruat" from aluminum corrosion.
When moisture gets mixed with acidic combustion wastes....carbon....oil....it drops PH over time and blooms like mold. It also makes tiny little pits from small debris like carbon denting as others have speculated....larger.

Also.....that first picture of your cam wear pattern.....the dark pitting.....in a very narrow ring like that is definately caused by acidic water damage. The overall wear pattern is at the surface. Pitting like that is sub surface and too deep to be caused by just the lofter edge alone.

It will be interesting to see the oul pump imsides and the insides of the case especially in the bottom of the oil pan. I would expect corrosikn from oil and water mixture.
This does not mean the case is bad......but its hard to clean up. Ray
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Wildthings
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PostPosted: Fri Mar 02, 2018 10:43 am    Post subject: Re: Type 4 engine forensics Reply with quote

The #1 and #3 cylinders look like they had water in them to me. You can see rust on the exhaust valves and on the rings as well as other corrosion. All the cylinders show signs of lead deposits as well, which since this engine is from fairly late in the lead age, means that it was probably run on high octane/high lead fuel.

A question for Furgo, once you split the case let us know if there are grayish deposits filling the bottom of the sump.

FWIW, the engine that is now in my '77 was originally from a '74 Type 4 car and I don't think it had been apart at all prior to my acquiring it, nasty gum and varnish inside and the cam looked worse than Furgo's. I originally just cleaned it up externally, resurfaced the lifters, resealed it, and put it in. It vibrated like crazy and I tried to keep the speed below fifty to keep the engine from self destructing. I did decide to take in from Oregon to Arizona and figured I would just stick to back roads wherever I could, but when time came to leave the east side of the mountains was a wintry mess, so I headed south on I-5 in heavy rain and snow. Luckily the traffic was pretty much going my speed. Pulling the Siskiyous I pushed it hard in high gear to keep from having to slow down below the vibration speed in third and then I cross to Susanville from Lake Shasta which did mean a goodly grind in third, I revved it enough to get it above the speed where the vibration occurred. By the time I leveled out, I found I could now run 55 without the vibrations being too bad, the engine was cleaning itself up a bit.

After I got to my destination I glued weights on the crank pulley and added washers under the flywheel bolts to minimize the vibration still more, but over the next couple of months, putting miles on it while running a 2-cycle mix in the tank, the vibration slowly returned so I removed the added weights and the vibration subsided a bit and if you got the speed up to 65 mostly disappeared. At this point my wife wanted to use the rig for a 250 mile highway run and I told her to push it as hard as she could, to keep the speed above 70 wherever possible and rev it hard if and when she had to use third. By the time she got back the vibration was pretty much gone.

Later when I removed the heads there was almost no signs of lead deposits, running a gas-oil mix and running the engine hard had removed them.


Last edited by Wildthings on Fri Mar 02, 2018 11:13 am; edited 1 time in total
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