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raygreenwood
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Joined: November 24, 2008
Posts: 21520
Location: Oklahoma City
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 Posted: Sat Dec 28, 2019 11:47 am Post subject: Re: Type 4 engine rebuild: take 3 |
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| SGKent wrote: |
the machine shop should have a jig that measures the rods for twist and bend.
Getting the rods to lay flat against each other isn't the test - you are testing for parallel. Use Len's trick with the rods bolted to 3 & 4 or 1 & 2. As to the pin fit, with oil on the pins and at room temp they should slowly fall thru with gravity. Not fast or binding. |
^^^^
One of the most common issues I have found with small engine machine shops that do not do high precision work like race engines....mostly over the past 15 years...so this is another one of those signs of the times....is habits of doing what they can get away with because a lot of what they are rebuilding range from lawn mowers to tractors to someone who just wants another 30-40k miles out of a straight 4 in their pinto. They are rebuilding basic worn out engines and not heavily damaged ones.
A lot of these shops have good basic equipment...like a good rod machine with a flat plate, built in indicators and a small and large end hone for re-sizing.
However....they have bad habits. Instead of checking each and every rod on a checking jig like SGKent noted....they quickly eyeball them on a flat granite plate. Not the same thing.
A quick or even not so quick re-size on the rod machine and the bore on the little end may now be slightly out of whack especially if the rod is twisted.
Add into this....the state of rod bushings these days. Its worthwhile to buy good known bushings and bring them to the shop. I have seen a few that simply oder from their jobber out of a catalog and if they come in oversized...then you get the shop screwing with the rod on teh honing machine until they can fit the oversized bushing. A shop with better habits...if they need to fit oversized OD bushings....would set them up on a mill...AFTER STRAIGHTENING to mill the small end for new bushings. Ray |
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orwell84
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Joined: May 14, 2007
Posts: 2539
Location: Plattsburgh, New York
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| Posted: Sun Dec 29, 2019 7:47 pm Post subject: Re: Type 4 engine rebuild: take 3 |
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| raygreenwood wrote: |
| SGKent wrote: |
the machine shop should have a jig that measures the rods for twist and bend.
Getting the rods to lay flat against each other isn't the test - you are testing for parallel. Use Len's trick with the rods bolted to 3 & 4 or 1 & 2. As to the pin fit, with oil on the pins and at room temp they should slowly fall thru with gravity. Not fast or binding. |
^^^^
One of the most common issues I have found with small engine machine shops that do not do high precision work like race engines....mostly over the past 15 years...so this is another one of those signs of the times....is habits of doing what they can get away with because a lot of what they are rebuilding range from lawn mowers to tractors to someone who just wants another 30-40k miles out of a straight 4 in their pinto. They are rebuilding basic worn out engines and not heavily damaged ones.
A lot of these shops have good basic equipment...like a good rod machine with a flat plate, built in indicators and a small and large end hone for re-sizing.
However....they have bad habits. Instead of checking each and every rod on a checking jig like SGKent noted....they quickly eyeball them on a flat granite plate. Not the same thing.
A quick or even not so quick re-size on the rod machine and the bore on the little end may now be slightly out of whack especially if the rod is twisted.
Add into this....the state of rod bushings these days. Its worthwhile to buy good known bushings and bring them to the shop. I have seen a few that simply oder from their jobber out of a catalog and if they come in oversized...then you get the shop screwing with the rod on teh honing machine until they can fit the oversized bushing. A shop with better habits...if they need to fit oversized OD bushings....would set them up on a mill...AFTER STRAIGHTENING to mill the small end for new bushings. Ray |
I think you are right on about that. It’s the sort of shop that does a little bit of everything from riding mowers to outboard motors and commonly found American motors. He seemed to find my requests for balancing pistons amusing and explained the factory GM motors can be as much as x amount off and run just great.
I was surprised that when I brought my heads in after damage from debris that he had just cleaned them up with a die grinder. I asked if he could do a shallow fly cut which he said he wasn’t set up to do.
He may have assumed given my lack of experience that my expectations weren’t very high and I probably wouldn’t know the difference anyway. For stock use VW engines are quite forgiving and maybe that measuring, machining and balancing to the extent we discuss in these forums.
I’m not sure if he is someone I could continue to work with. Maybe if I’m more specific in what I ask. But checking rods for straightness, relishing and balancing both ends seems specific enough. I also provided the bushings.
A quick question:
What size V blocks do I need. I’d rather not make them. They aren’t very expensive.
Thanks |
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SGKent 
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Joined: October 30, 2007
Posts: 41031
Location: Citrus Heights CA (Near Sacramento)
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| Posted: Sun Dec 29, 2019 9:35 pm Post subject: Re: Type 4 engine rebuild: take 3 |
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post your location in your avatar.
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orwell84
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Joined: May 14, 2007
Posts: 2539
Location: Plattsburgh, New York
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| Posted: Mon Dec 30, 2019 4:50 am Post subject: Re: Type 4 engine rebuild: take 3 |
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| I am in northern NY state Plattsburgh area. I still have to change it in my avatar. |
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calvinater
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Joined: September 06, 2014
Posts: 3333
Location: 802 The Pointless Forrest
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| Posted: Mon Dec 30, 2019 5:42 am Post subject: Re: Type 4 engine rebuild: take 3 |
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Heading to the airport on the first around ten am need any help?
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SGKent
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Joined: October 30, 2007
Posts: 41031
Location: Citrus Heights CA (Near Sacramento)
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| Posted: Mon Dec 30, 2019 9:40 am Post subject: Re: Type 4 engine rebuild: take 3 |
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| orwell84 wrote: |
| I am in northern NY state Plattsburgh area. I still have to change it in my avatar. |
Control Panel at the top, Enter it in Location and hit submit. Others need to know when you are looking for machine shops etc.
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orwell84
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Joined: May 14, 2007
Posts: 2539
Location: Plattsburgh, New York
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| Posted: Mon Dec 30, 2019 10:35 am Post subject: Re: Type 4 engine rebuild: take 3 |
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| calvinater wrote: |
| Heading to the airport on the first around ten am need any help? |
Thank you so much for your kind offer, but I will be out of town. |
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orwell84
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Joined: May 14, 2007
Posts: 2539
Location: Plattsburgh, New York
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| Posted: Mon Dec 30, 2019 5:01 pm Post subject: Re: Type 4 engine rebuild: take 3 |
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So I repeated my runout measurements on the crank moved the gauge around, etc.
With the crank in the case supported by the bearing shells on #1 and 3 I got just under .002 for the #2 journal and 0 for number 4.
Does this indicate a bent crank? |
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SGKent
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Joined: October 30, 2007
Posts: 41031
Location: Citrus Heights CA (Near Sacramento)
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| Posted: Mon Dec 30, 2019 5:13 pm Post subject: Re: Type 4 engine rebuild: take 3 |
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| orwell84 wrote: |
So I repeated my runout measurements on the crank moved the gauge around, etc.
With the crank in the case supported by the bearing shells on #1 and 3 I got just under .002 for the #2 journal and 0 for number 4.
Does this indicate a bent crank? |
all the ones I've done indicate 0.000 .
Mark the high spot with a sharpie, move the Vee blocks to another sturdy table and do it again. See if the high spot is the same.
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Clatter
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Joined: September 24, 2003
Posts: 7551
Location: Santa Cruz
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| Posted: Mon Dec 30, 2019 11:38 pm Post subject: Re: Type 4 engine rebuild: take 3 |
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You don’t need ‘V’ blocks,
You can measure in the bearings in one case half.
I have never had a crank that wasn’t dead on 0 either.
Sounds like your crank is bent.
If your .002 is ‘noise’ that’s one thing; a very rough journal to be ground.
But if it’s going humpity hump in the same spot every time around it’s bent.
Putting your indicator on different journals,
And pulling a main or two, to support the crank in certain ways,
Then measuring in a different spot can tell you which way and where the crank is bent.
For example,
Pull the center main and small snout bearing,
Then measure runout on the center main journal.
Then at the snout journal..
Or leave the center main and the rear (flywheel) main, and measure the snout, or front main.
Get a feel for Direction the crank is bent to learn how and where it deviates from true.
That way you’ll have confidence that it is indeed bent.
Not that there’s anything to really be done about it at home.. 
A real crank shop like Demello (RIP) or DPR can straighten a bent crank for a reasonable fee.
It used to happen more than you’d think.
What with stock cranks being cheap and reasonably plentiful it might not be worth it.
If you end up having a hard time finding another it might not.
Might try EMW or MoFoCo?
Core motors still show up on Craigslist round here.
FWIW your machinist sounds like hack from your description..
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orwell84
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Joined: May 14, 2007
Posts: 2539
Location: Plattsburgh, New York
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| Posted: Tue Dec 31, 2019 9:32 am Post subject: Re: Type 4 engine rebuild: take 3 |
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Quick question...Can I pull the timing gear off with a regular 3 arm puller? I know there is a tool for it, but for the same money I can get a 12 ton press from HF, which would be more useful.
Once I pull the gear I can try it supported on different journals...but...I have tried this measurement a bunch of different ways and marked the crank...it blips in the same spots, the indicator moves in the same way every time.
I think it started out as a turd of an engine, which isn’t to say it didn’t run decently even as a GEX engine. As has often been said, these engines can be very forgiving.
I will do my best to confirm that the crank is indeed bent. Same for the rods. I will have a more experienced friend double check for me when we both can find the time.
I was looking at the website for DPR machine. They sell reconditioned cranks, rods etc and from what I have read are quite well regarded. There is also EMW for reconditioned parts. It might be worth it rather than dicking around with the same bent up crap. They would be great someday in a sweep the floor engine...one that it doesn’t matter if it blows because it wouldn’t take any good parts with it. The kind of engine you try to break for pure sport but never does.
I ordered a machinist straight edge flat plate and dial bore indicator. I will be checking the case next. |
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Abscate
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Joined: October 05, 2014
Posts: 22670
Location: NYC/Upstate/ROW
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| Posted: Tue Dec 31, 2019 2:33 pm Post subject: Re: Type 4 engine rebuild: take 3 |
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Let me know if I can help down here in Albany. I do swing by on the way up to MONTREAL or to the Lake of Champlions
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cmonSTART
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Joined: July 15, 2014
Posts: 1915
Location: NH
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| Posted: Tue Dec 31, 2019 2:55 pm Post subject: Re: Type 4 engine rebuild: take 3 |
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| orwell84 wrote: |
| Quick question...Can I pull the timing gear off with a regular 3 arm puller? I know there is a tool for it, but for the same money I can get a 12 ton press from HF, which would be more useful. |
When I did my first rebuild on my 78 I decided to get the 12 ton press and figure it out. It worked great, though I had to get a bit creative with some random bits of steel I had laying around, but I figured the press was worth figuring it out a bit.
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SGKent
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Joined: October 30, 2007
Posts: 41031
Location: Citrus Heights CA (Near Sacramento)
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busdaddy
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Joined: February 12, 2004
Posts: 51155
Location: Surrey B.C. Canada, but thinking of Ukraine
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| Posted: Tue Dec 31, 2019 3:36 pm Post subject: Re: Type 4 engine rebuild: take 3 |
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I use a 3 arm puller, but a press would likely get more use for other jobs around your shop. You'll need some plates with a sharpened edge like the bearing splitter SGK posted though. Maybe it would be easier to rent a 3 jaw from a local tool rental store?
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Wildthings
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Joined: March 13, 2005
Posts: 50353
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| Posted: Tue Dec 31, 2019 4:11 pm Post subject: Re: Type 4 engine rebuild: take 3 |
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| busdaddy wrote: |
| I use a 3 arm puller, but a press would likely get more use for other jobs around your shop. You'll need some plates with a sharpened edge like the bearing splitter SGK posted though. Maybe it would be easier to rent a 3 jaw from a local tool rental store? |
There is not much to grab hold of so some pullers will not work well. A bearing splitter and the correct two jaw puller to grab the splitter will work. |
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orwell84
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Joined: May 14, 2007
Posts: 2539
Location: Plattsburgh, New York
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| Posted: Thu Jan 02, 2020 8:31 am Post subject: Re: Type 4 engine rebuild: take 3 |
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I just ordered the tool. No sense risking gouging up the journal with random crap tools just to get at it a few days earlier. When I get the gear off, I can do some more checks on runout. I will also check the rods for parallel as recommended by Len. My machinist ruler should arrive today so I can check the case deck. I will also put the halves together and have a look at the bearing saddles and gaps in the mating surfaces.
If things are still looking iffy, I would seriously consider getting a reconditioned crank and rod set from DPR crank and see how much of the work they could do in terms of grinding a crank to a set of new main bearings and a completely rebushed and balanced set of rods. |
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SGKent
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Joined: October 30, 2007
Posts: 41031
Location: Citrus Heights CA (Near Sacramento)
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| Posted: Thu Jan 02, 2020 12:14 pm Post subject: Re: Type 4 engine rebuild: take 3 |
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| orwell84 wrote: |
I just ordered the tool. No sense risking gouging up the journal with random crap tools just to get at it a few days earlier. When I get the gear off, I can do some more checks on runout. I will also check the rods for parallel as recommended by Len. My machinist ruler should arrive today so I can check the case deck. I will also put the halves together and have a look at the bearing saddles and gaps in the mating surfaces.
If things are still looking iffy, I would seriously consider getting a reconditioned crank and rod set from DPR crank and see how much of the work they could do in terms of grinding a crank to a set of new main bearings and a completely rebushed and balanced set of rods. |
Marine Crankshaft in Santa Ana is the best solution to crankshafts for a bus. I have not used them but the big boy racing crowd* ALL named them as #1. They do polishing, balancing, and straightening too. Don't know who does quality rods but you could ask them. http://www.marinecrankshaftinc.com/
* IMSA, NASCAR, SCORE, and SCCA folks who are winning their races and classes. I took a poll of some of the winning teams a couple years ago and this is who they all recommended for the type work we do.
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Last edited by SGKent on Thu Jan 02, 2020 4:44 pm; edited 2 times in total |
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Clatter
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Posts: 7551
Location: Santa Cruz
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| Posted: Thu Jan 02, 2020 3:58 pm Post subject: Re: Type 4 engine rebuild: take 3 |
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This press is just too cheap not to get..
https://www.harborfreight.com/20-ton-shop-press-32879.html
At 20 tons, it will do most things a bus owner might need to do.
You could also do a transaxle with it one day if you wanted.
Their 12-ton model, I was worried the bed is too narrow for a type 4 crank to fit thru.,
The 20-ton is also too small if you have a counterweighted crank FWIW..
So good that you got a gear puller, you can run a counterweighted crank.
There was a 'Super Coupon' for that press, where it was only like $120 IIRC?
It was in the back of HotVWs a few months back..
DPR was who did cranks for Jake BITD, might still be the case, even?
Have done a half-dozen or so motors with DPR cranks m'self,
And all have been perfect.
If that crank is indeed .002" bent out of wack,
I'd shitcan that thing so it doesn't accidentally end up in some poor guy's motor.
Or send it to Jose at DPR..
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orwell84
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Joined: May 14, 2007
Posts: 2539
Location: Plattsburgh, New York
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| Posted: Thu Jan 02, 2020 9:03 pm Post subject: Re: Type 4 engine rebuild: take 3 |
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Well shit...
My case and dial indicator were set up on an old Black and Decker workmate bench. The magnetic dial indicator stand was affixed to a 1/8 hunk of channel clamped to the bench and the case was well supported. It seemed really stable but...
when I rigged up the dial indicator to the case itself, the runout almost completely went away...maybe like .0002 and it’s still a pretty janky setup that I could easily make more stable. Jeez...
Sorry to have yanked your chains about a bent crank. I guess I learned something though... |
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