TheSamba.com :: View topic - Getting the ball rolling '73 Standard

Tue Nov 10, 2009 1:20 am

PatterBon wrote: I only measured my deck height only when my cylinders were held in by hand, and with the water in the oil, I don't think that helped the bearings on the rod. I'm going to clean the heads and the pistons to see if they are ok..I didn't run the engine long mind you. I also did a rough estimation on head torque when I put them back on :oops: I didn't have the torque wrench when I was putting the heads back on..do that could have been another contributing factor. Rob and Dave's www.vw-resource.com said that an over torqued head can make as much of a difference of I want to say .02" I believe...So if my crank journals are still looking alright, then I'm going to get new rod bearings on Wednesday, along with getting a torque wrench especially for torquing the heads back down again.

before you do that, find out WHY you got water in the oil. It's not something you usually get with aircooled engines :shock:

If your oil is really thin, smell it for gas. the failure mode of a mechanical fuel pump is usually one of two things. Pumps no gas at all or pumps it all into the case. YOu absolutely must make sure you have the correct pump, correct pump pedestal and rod and above all, correct fuel pressure. One aftermarket pump I have had put out over 6PSI with 10 gaskets underneath it!!!. 3 to 3.5 PSI max with no more than a couple or three gaskets underneath or something is wrong. Just because its the one that it came with does not mean that it's correct or that it's working properly.

Tue Nov 10, 2009 3:19 am

What was the deck height when you measured it?

I have seen where the squish area was visible, but the entire piston top was coked some . . . but never so clean outside of the squish. Man that looks WAY close.

I would absolutely recommend having someone mic your crank, don't just do a visual on it - that is the heart of your engine and if something is wrong that you can't see without fine measurement you'll be doing this all over again way too soon.

Excellent effort . . . I am never in this forum, but your story caught my attention - and was a interesting read so far.

Good luck!

Thu Nov 12, 2009 4:18 pm

Hey guys, sorry its been awhile since I've updated..I'm about to go back out there and start work again..Today is the first day where it isn't down pouring..and they're calling for some snow tomorrow! :shock: But I'll post some more pictures tonight..and I didn't get to go to the VW shop..it was closed :x ..So I may go this weekend. and the flywheel will still be on the pictures tonight because my helper...*cough Invisible Stuff cough* is to caught up in the new Call of Duty..Hopefully this weekend or tomorrow even I'll have the new bearings and a better idea of what the condition of the crankshaft is in.

Thu Nov 12, 2009 5:43 pm

Wouldnt worry too much about deck heigth... your reusing the P/Cs,which were in spec before...the metal on the screen is troubling,once you split the case it will become clear what caused it. Make sure you completely clean the case before re assembling,and replace the oil cooler,its almost impossible to get all the debris out of it. Hang in there,you see how fast it goes the second time,just relax and do it right...

Thu Nov 12, 2009 6:06 pm

Here's the #3 piston after cleaning.

Looks to be in pretty good condition..there isn't any evidence of damage..And what is that brightish circle?

And here's what I ended with today..tomorrow Invisible Stuff will help me out with removing the gland nut and I'll split the case!

And one more goodie..for Fattie :D

The #3 rod was so loose it wasn't funny :? But at least now I've found the cause of the knocking..Now it's just hoping and praying that I didn't screw up the crankshaft any.

Thu Nov 12, 2009 6:46 pm

PatterBon wrote: Looks to be in pretty good condition..there isn't any evidence of damage..And what is that brightish circle?

my guess is probably where the sparkplug is

Thu Nov 12, 2009 7:16 pm

Bearing missing out of #3 rod allowed the piston to "follow" up to the head face....it aint the combustion chamber....bearing(or lack of)caused your problem..

Thu Nov 12, 2009 7:57 pm

PatterBon wrote: And one more goodie..for Fattie
thank you ... I was getting bored ;)

Thu Nov 12, 2009 8:34 pm

Do you have someone local to look at the crank? Hopefully it just needs a polishing, but who knows.

Was it knocking right away? If not, makes you wonder how long it was run outside of your test fire.

Thu Nov 12, 2009 10:08 pm

Gerg...he reused P/C's but freshened everything else up,fired it up and knocked hard rite off the bat....figured he spaced out a rod bearing...it would kind of explain the head carbon pattern,but the metal in the oil is worrisome..Patterbon,did you change the main bearings you pinched?

Fri Nov 13, 2009 5:31 am

if you remember, the combustion chamber shaped coking was on two cylinders, not just the one.

Something is amiss more than just a single rod bearing.

Was there a mysterious ring lying on the floor when you took it apart that you didn't know from whence it came?

All I'm saying is, if you reused the pistons and cylinders, you must have taken them off. When you put them back on, something is different that caused the piston to get close enough to the head on 3 and 4 (check the carbon patterns guys) that they had a momentary illicit kiss.

Something has caused your cylinder to sit further in the case or the head, whether it's the lack of a paper gasket and sealant or a big copper sealing ring in the head.

Your cylinder should stick out past the piston by 1 to 2 mm. If it is less than that, you need a copper ring in the head to prevent the two having a brief affair

Even with a really tight deck of 1mm the cokeing up on a piston will cover the whole piston, not shaped to a combustion chamber.

your deck is hosed for some reason causing the rod bearing failure, not the other way around

Fri Nov 13, 2009 9:41 am

Marv [UK] wrote: if you remember, the combustion chamber shaped coking was on two cylinders, not just the one.

Something is amiss more than just a single rod bearing.

Was there a mysterious ring lying on the floor when you took it apart that you didn't know from whence it came?

All I'm saying is, if you reused the pistons and cylinders, you must have taken them off. When you put them back on, something is different that caused the piston to get close enough to the head on 3 and 4 (check the carbon patterns guys) that they had a momentary illicit kiss.

Something has caused your cylinder to sit further in the case or the head, whether it's the lack of a paper gasket and sealant or a big copper sealing ring in the head.

Your cylinder should stick out past the piston by 1 to 2 mm. If it is less than that, you need a copper ring in the head to prevent the two having a brief affair

Even with a really tight deck of 1mm the cokeing up on a piston will cover the whole piston, not shaped to a combustion chamber.

your deck is hosed for some reason causing the rod bearing failure, not the other way around

I'm sorry, I completely disagree.

First of all, that paper gasket is nowhere close to thick enough to cause an issue if it's missing. Most of us don't use those, but instead use sealant.

Secondly, it is a 1600 dp, correct? They didn't have the copper rings in the heads from the factory. So unless the tops of the cylinders were machined to be shorter, the head and cylinders have nothing to do with it. Bad bearings, he said there was water in the oil. That will wipe out bearings very quickly, especially if the bearings were marginal to begin with.

PatterBon, get the crank looked at by a machine shop, get the proper bearings for it, get the pistons and cylinders back on it, then take some measurements of the tops of the pistons at top dead center before you put the heads on. This will tell you everything.

EDIT: If there were a deck problem or the cylinders were sunk/too short, then the engine would not have turned over completely and you would have bent connecting rods. Beat up bearings or wrist pins are the only things that would allow the piston to reach farther toward the head and still allow the engine to make a complete revolution.

Fri Nov 13, 2009 10:40 am

When heads are remanufactured they are sometimes fly cut as well,restoring the cylinder sealing surface. This can result in condition where the cylinders need to be shimmed to maintain compression ratio.The head in the picture appears to have the sealing ridge intact,which generally means it hasnt been flycut.The crankcase deck appears to be stock as well.The piston top markings indicate the P/C's are quality,cheapos usually just have the offset arrow.I believe the deck heigth is correct. We wont know squadooche till we find the root cause.One thing to consider,he pinched the bearings when assembling the case halves, he didnt line up the bearings and the dowel pins.He separated the case and reset the bearings but didnt say if he changed the distorted one....

Fri Nov 13, 2009 2:16 pm

The distorted one was not replaced, but at the same time, I didn't torque down all the crank case nuts before I noticed the problem, because I was trying to rotate the crank the whole time. I do indeed know that I over torqued the heads, but on Cylinders 1 & 2 there wasn't coking like there was on the 4 & 3 cylinder..So I do know that the 1 & 2 pistions were fine and the head wasn't burnt at all. Also, I know (or at least it seems obvious) that my #3 Rod Bearing was either gone or close to it when I took the pistons off because I could pull it back and forth as though the two nuts that hold it together weren't torque on all that much. I won't know until later today what the condition the crank is in..Also on the #4 rod, I could pick it up, and it would stay in place and not fall back down..Is this something to be concerned about?...And lastly..When it was running, it ran strong, there was no hesitation on acceleration and I had good compression (I didn't compression test it, but turning it by hand, you could feel how good the compression was) So it seemed to be in good shape as far as how it ran, but it wasn't mechanically sound.

Fri Nov 13, 2009 3:09 pm

I'd also suggest having the rods looked at when you take the crank. They make sure they are still 'round' among other things.

I would definitely look at #4 after what you said. I have never assembled one that didn't rotate freely and fall on its own weight.

Fri Nov 13, 2009 4:08 pm

Paul Windisch wrote: Marv [UK] wrote: if you remember, the combustion chamber shaped coking was on two cylinders, not just the one.

Something is amiss more than just a single rod bearing.

Was there a mysterious ring lying on the floor when you took it apart that you didn't know from whence it came?

All I'm saying is, if you reused the pistons and cylinders, you must have taken them off. When you put them back on, something is different that caused the piston to get close enough to the head on 3 and 4 (check the carbon patterns guys) that they had a momentary illicit kiss.

Something has caused your cylinder to sit further in the case or the head, whether it's the lack of a paper gasket and sealant or a big copper sealing ring in the head.

Your cylinder should stick out past the piston by 1 to 2 mm. If it is less than that, you need a copper ring in the head to prevent the two having a brief affair

Even with a really tight deck of 1mm the cokeing up on a piston will cover the whole piston, not shaped to a combustion chamber.

your deck is hosed for some reason causing the rod bearing failure, not the other way around

I'm sorry, I completely disagree.

First of all, that paper gasket is nowhere close to thick enough to cause an issue if it's missing. Most of us don't use those, but instead use sealant.

Secondly, it is a 1600 dp, correct? They didn't have the copper rings in the heads from the factory. So unless the tops of the cylinders were machined to be shorter, the head and cylinders have nothing to do with it. Bad bearings, he said there was water in the oil. That will wipe out bearings very quickly, especially if the bearings were marginal to begin with.

PatterBon, get the crank looked at by a machine shop, get the proper bearings for it, get the pistons and cylinders back on it, then take some measurements of the tops of the pistons at top dead center before you put the heads on. This will tell you everything.

EDIT: If there were a deck problem or the cylinders were sunk/too short, then the engine would not have turned over completely and you would have bent connecting rods. Beat up bearings or wrist pins are the only things that would allow the piston to reach farther toward the head and still allow the engine to make a complete revolution.

You read 48 pages, I didn't. Couldn't be arsed.

Whatever the cause, numbers 3 and 4 have hit the head, not just number 3. THis is the reason why I said deck issues. If number 4 hasn't gone already, it was only a matter of miles

FYI, the mexi heads on some mexi engines did come with copper head gaskets as did some of the VEGE engines. In addition to this, the main way of making a badly made engine last long enough to get through a limited warranty is to make it really low compression (in the 6's) so they don't overheat and there are no deck issues. This is either using big barrel shims and/or copper head shims. the head shows a seating surface but I've seen heads with a seating surface and a copper shim as the ridge was barely there. machined down but still there.

having just read patterbons latest post, I'm not surprised the engine blew up.

At the end of the day, if #3 was on it's way out, why the hell did you put it back together? with #3 and #4 going south it was only a matter of time.

Oh, and the engine would have turned over if the contact is very slight and cold oil pressure was high. It's when it warms up and the bearings get slacker that things loosen up and the contact really gets going. It's possible that there was no contact to begin with, just when things loosen up when they get warm. the first thing to go is the rod bearing. Bent rods happen when things keep going after rod knocks or cranks break.

FWIW, your man has got what he has got, the cause is irrelevant. first thing is tear down and inspection and see what is in there. crank main and rod journals, case bearing seats and the conrods. chuck the bearings, all of them and start again.

Fri Nov 13, 2009 4:43 pm

I didn't know that the rod bearings were going out or else I would have replaced them. But now that I can see that #3 was so far gone and #4 is sticking..I'm glad I didn't dismiss it as just rebuild engine noise. But # 1 & 2 looked fine, I'll replace all of them, but it makes me curious why just 3 & 4 were bad...I think that its an over torque issue partially, along with the rod bearing being so far gone...Gland Nut isn't coming off today so tomorrow you can expect updates with pictures and videos of what I found.

Fri Nov 13, 2009 5:01 pm

Regardless of the disagreement above, checking the deck is something you should be doing on assembly anyway . . . so let us know what you find.

Fri Nov 13, 2009 5:19 pm

Alright..will do, here's just another really quick video I just took of how bad #3 is and the problem with #4

Fri Nov 13, 2009 10:34 pm

I'll be in Gig Harbor next week again and have several engine building tools that go unused most of the time . . . be glad to lend you a few if you like.