Cracked Bolthole on Block for Starter

cucvrus

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I do not think it is even possible to put a flex-plate on backwards in a CUCV and get everything lined up. I did see a dowel hole in the flex-plate that would not allow the dowel pin to go in and it was being forced into the. I seen that on a few new flex-plates. The center pilot hole never. How would the torque converter bolts attach with the weights against the torque converter? I don't see it happening.
 

cwc

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I had to replace a starter solenoid on one of the M998s; it a non-runner and the fuel pump was missing, which was a clue about the starter solenoid - probably somebody took the fuel pump off to get to the starter but did not follow through. Anyway, I had not worked on a GM starter with the shimming considerations in a while and was a little concerned about getting it right. So I left the solenoid off the starter and connected some heavy wire to the linkage; then I could pull on the wire and make the gear engage to check the fit to the ring gear, push it in and out of engagement, etc. That worked pretty good to check it, and the engagement is smooth...went back with the shim that it came with.

If it is just grinding and not engaging, maybe your solenoid is weak; it has to pull against a pretty heavy spring doesn't it? Or if it does not want to disengage, maybe the spring is broken or weak?
 

cucvmule

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I have been a G.M. Guy forever. I have done the starter thing every way you can except sleep with it. I use a remote starter switch , Sun equipment, yes I have Some Age. cwc has a very good idea, you have to look at the engagement to see if they are square to each other. Yes I have single side shimmed before, bend a ninety and placed. Starter bracket shall be placed on EVERY starter, gas and especially diesel.

Unfortunately 6.2 has this problem of cracking the starter bolt casting area. You have the right direction, the starter bracket is also used to help align and square the starter.
If there is not enough clearance the starter will bind. The first thing I would do is take the starter drive, either a new in the box or off the starter and mesh it on the flywheel.
Look at the clearance and make sure they are compatible. Their are several different drives, the starter solenoid will have a definite effect. Even though it works does not mean that it is able to do the job. I just had one sticking and replaced the solenoid and spring, problem gone.

I have over the years collected 20 plus starters over the years and when fabricating for engine installs, use different starters for fitment. High torque, regular duty, gear reduction the list goes on.

Just because the part seller says it is the right one does not make it so. Original equipment part new or used is the way to go. I would make one before I would put a Chinese made part on my equipment.

I hope this helps, but to put more than two shims on there is a definite problem. Ask for a replacement starter, starter drive, or solenoid. It also matters how you torque it down, evenly or which one first. Gooood Luck!!!
 

zdubz

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I ended up getting a 3rd starter. This one has the same problem of not being able to disengage, even when shimmed up to 1/8th inch. It sounds best when it is not shimmed at all. I am going to get some new bolts and then probably try and see if shimming one of the bolts more will help.

The method I use to check pinion engagement and compatibility is to loosen the 2 solenoid bolts, mount the starter and then manually engage the solenoid by hand wherefore bringing the gear out and showing me where it will land and what the clearance will look like.

This 3rd starter seems to fit better than the other 2 but being that it has the same disengagement issue I suspect that when I drilled and tapped threads into the block that it is skewing the placement vertically somehow. (Had a cracked bolthole on the block, and I didn't see any other option) Poor thing's been sitting for a year already and I'm running out of advice from local GM and starter shops etc... Appreciate all of your input!
 

zdubz

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All of the starters I've tried technically engage and turn the plate, its the dis-engagement that worries me. I suppose that once the plate is turning on it's own that it will assist in disengaging the pinion and then the plunger will just pull it back in, but I'm a novice on starters and don't know how a perfect operation looks like anyway.
 
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cucvrus

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Lets not complicate the issue. If it is bolted to a diesel torque converter it has to be a diesel flex plate. And if he manually engaged the starter drive gear into the flex-plate teeth and it fit. It will fit no matter how many teeth it has. I am all for firing it up. Be careful.
 

m816Buch

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do you know anything about the motor being replaced from a different vehicle?? Was the starter making noise when you bought it or did it just start?? Some GM engines have a different crankshaft for manual transmissions, the flywheel flange is thicker. Also if tranny torque converter was swapped from another trans as in a rebuild, converter center bulge can hit crankshaft then when you bolt the flywheel to the converter it bows the flywheel.
 

cucvmule

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Pilot bearing issue? Maybe sticking out? I wasn't aware of different crank flange thickness.

I agree with cucvrus, do not make it complicated. If the starter is shimmed an 1/8 inch, wow that is a lot, it is trial and error at this point. Try it and be ready to pull cable, turn off key. Pull fuel pump power lead to see if starter engages and disengages.

If there is one good bolt hole that has to be your pivot point. the drilled hole is a hail mary and should be used as an "adjustment hole now," along with starter bracket.
 

Kaiser67M715

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Lets not complicate the issue. If it is bolted to a diesel torque converter it has to be a diesel flex plate. And if he manually engaged the starter drive gear into the flex-plate teeth and it fit. It will fit no matter how many teeth it has. I am all for firing it up. Be careful.
The "diesel" torque converter is the same low stall converter used on big blocks, 305's and V-6 got a high stall, most others got a medium stall. Therefore it is possible to have the incorrect flexplate-been seeing it more lately, the starter gear will look like it meshes with the flexplate, and heck, if you rolled the starter gear all the way around the FP, off the vehicle, it would work, but on the vehicle is another story. It will eventually jam and fail to disengage. Count the teeth to be sure. It's cheaper then a starter.

There is no difference in cranks between manual and automatic engines-too much cost for GM to have two different cranks, there is a difference in starters, a "big mouth" and "small mouth" the small mouth is rarer, and was only used on automatic engines, I think GM stopped using the small mouth to save on production cost.

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cucvrus

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diesel flexplate.jpg350 flex plate.jpgI know all the gas engines I remove for salvage have 3 bolt torque converters. The 6.2 have 6 bolt torque converters. I am NOT an expert but have removed a fair share of engines. Gasoline small and big blocks and many 6.2 and 5.7 GM diesels in my time. What would decide if a flexplate/torque converter has 6 bolts or 3 bolts? I am relying on memory as it has been a few years since I removed a gas engine. I did a 700R removal last winter from a 305 Chevy and it had 3 bolts torque converter to flex plate. The left is a 6.2 diesel and the right is a 350 gas engine. Both fit 1984 K30 pick up truck. I may have over looked that the flex-plate has 6 holes. But I thought they would not align with the diesel torque converter. The 6.2 has the weigh welded on the flex-plate.
 

zdubz

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Pilot bearing issue? Maybe sticking out? I wasn't aware of different crank flange thickness.

I agree with cucvrus, do not make it complicated. If the starter is shimmed an 1/8 inch, wow that is a lot, it is trial and error at this point. Try it and be ready to pull cable, turn off key. Pull fuel pump power lead to see if starter engages and disengages.

If there is one good bolt hole that has to be your pivot point. the drilled hole is a hail mary and should be used as an "adjustment hole now," along with starter bracket.

This 2nd and 3rd starters do not experience run on at all but what I had been doing with the starter that did do that was just keeping the terminal clamps loosely on the batteries and unplugging them quick. No matter - I'm not putting that starter back on again anyhow. What is a pilot bearing?
 

cucvrus

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A pilot bearing/bushing goes in the end of the crankshaft and on a manual transmission the tip/shaft of the manual transmission rides in the bushing/bearing in the rear of the transmission. That is not the issue on a stock automatic transmission. That is why I said do not complicate and cloud the issue. I think you are on the right path. Continue and report back. Have a great day. Good Luck.
 

Rvitko

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If it doesn't work my guess is wrong flexplate, cracked bolthole or not, if it is torqued to specs against a flat surface and the support bracket and starter are correct, the parts will be in the same alignment, if two gears get stuck and are in the same plane, the only realistic option is one has the wrong number of teeth, they may mesh but get out of time and jam. One thing I've learned the hard way on everything is do it yourself because you don't need to pay someone to screw up what you can screw up just as well.
 

cucvrus

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One thing I've learned the hard way on everything is do it yourself because you don't need to pay someone to screw up what you can screw up just as well.

I agree. But to a point. If you do it yourself IMHO you can assure the job is done right. Do your very best to replace parts with the right/correct parts and fix only the issue that you are targeting one issue at a time. That way when it works you know you have fixed it and if it don't work you know you did not fix it right or you have replaced and serviced the wrong part. Another thing is if it is NOT broke don't fix it or change it. Let it work and only fix it if it don't work. Replace only the needed parts and don't try to redesign a working for 30 year design. It just creates issues down the road.
 

zdubz

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Update:

I had a mechanic (who was in the service and worked on these rigs) -come and give mine a look. It's been since 1987 that he has had his hands on one, but he is fairly positive that my problem is entirely electrical and due to some starter relay which is apparently not allowing either of the new starters to pull the Bendixon back in. Does this jive with any of y'alls experience or knowledge? Thanks in Advance.
 

Kaiser67M715

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These starters don't use the typical Bendix drive, but rather a spring plunger to engage the starter gear- the momentum of the flywheel will cause the starter gear to retract. Your issues lies elsewhere. Have you checked the flex-plate for straightness?

Possible issue is that upon redrilling the holes, you don't have enough engagement, and that is causing it to bind up.

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gringeltaube

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I tend to believe that your main issue is that after just cranking the engine - but no start. the Bendix gear stays engaged...?? But not, after the engine actually started and ran???
From playing with these engines for a while... I'd say that on most of these 100-Dollar gear reduction starters the Bendix will stay engaged, either until the engine starts firing or if you turn the crank manually. A tiny fraction of one tooth on the flywheel is sufficient to have it released.
And that happens even with four 100%-new batteries hooked up in parallel and almost no voltage drop while cranking; flywheel teeth greased- or dry; extreme shimming- or no shims at all...!
When it first happened to me I was concerned (obviously) - now I just leave it alone. Starter does its job and that's all I want. I know that that thing will retract as soon as the engine catches; so no problem.
 

zdubz

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Kaiser67M715 and gringeltaube,

If what you're saying is true that the momentum of the flywheel (flexplate in this case) will cause the starter gear to retract, then I should not have any problem at all.
You see, I have had my plugs out and my injector solenoid wire disconnected for this process because I was worried about getting the starter to match perfectly and worried thinking that the plunger should come back out when I am done cranking.

To reiterate in the form of another question: If the flexplate does not or can not get it's own momentum from the engine turning (like right now with plugs out etc..), would it actually be EXPECTED for the plunger to stay engaged in the teeth of the ring gear? Because if that's the case than I am about to be a very happy man because I've only been worried that it will stay in there and destroy the new flexplate I installed.
 
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