VCCA Home Forums GENERAL DISCUSSION What did you do with your vehicle today? 1930 Chevy Sport Roadster

I traded a bike for this roadster last month and took a couple of trips around the block. I'm still trying to decide on a plan of attack on what I want out of it but I figured I would address some issues. My two major concerns are a massive oil leak from behind the crank pulley and a leaky gas tank. I sent the gas tank to my buddy that builds chopper gas and oil tanks to have it recreated. I should have it back with a nice copy in a few weeks. The oil leak I'm fixing myself.

So today, yesterday actually, I started pulling the front end back off. I hoped to get by just pulling the radiator but my puller is too long and runs into the front pan and guide for the crank. Not much progress and it looks like I'm pulling the rest off next weekend.

Hello Primo,

So 1930 was the first year for a "vibration dampener" on the Chevrolet 6 engines. It is not like modern dampeners in that it is composed of 2 separate pieces connected by internal springs, not rubber. When pulling this dampener from the engine it is important to follow a different procedure than any you might be used to. If I remember correct the 2 bolt holes are actually designed to lock the 2 parts of the dampener together instead of being to pull it off. Then you use an external puller to pull it off instead of a "crows foot" type puller. Same when reinstalling the dampener. You need to put 2 short 3/8" bolts in those holes to lock it together and a 1-1/2" or 2" pipe over the hand crank spiral so as to not damage the spiral when pounding it back on. A large block of wood used outside of that spiral will work as well.

How much oil are we talking about? If it is a slight drip that may not be all that problematic. If it is a fair sized amount then you probably should investigate. The assumption is that you want to pull the front timing cover off. Bear in mind you will have to pull the oil pan as well. There is no actual seal on the front of these engines just an oil "slinger" to keep the oil squirting on the timing gear inside the engine. That timing gear cover has 3 bolts that go through the front main bearing section of the block from inside the pan. One of those bolts also retains the front main bearing bolt lock. The oil pan has its own sequence of being reinstalled so as to not plug the distribution tubes that supply oil to the oil pan troughs.

Please keep the forum posted as to your progress.

Art

Hey, thanks for the tips. I'm seeing a massive amount of oil, enough that I can clearly follow my short run to the end of the block and back.

Thanks for the tips I have both types of pullers but can't find a 30-service manual. The ones I have are from 32 and 34, they don't go into much detail. I did order all of the related seals and gaskets, and I figured the pan may be coming off. Looking at the images I was going to use some spacers to cinch up a crows foot puller so the two pieces are held together.

I found my leak. It wasn't an easy fix like I hoped. I pulled the harmonic balancer and started it up, no visible leaks. Stuck my head underneath and saw this crack. I haven't dropped the pan yet but I'm pretty sure that it is part of the engine casting. Sorry for the bad pictures, I was stuck up underneath trying to get them.

Front of engine:



Coming into the back of the timing plate:




That massive crack is leaking.

So looks like that is my front crank cap, anyone know where I can find one? Trying to just run this engine until I can get a fresh engine built. My book says casting 836287. Assuming part number 362781.

Picked up a bearing cap from Dave39MD here on the vccachat. Went ahead and pulled the oil pan, the old bearing fell out with the cap. There were no shims up there, so it must be on the loose side. I wasn't hearing any knock like the manual says I may if there is too much clearance I guess I need to order some plastigauge and check clearances when I reassemble. I understand I should line bore it but I don't feel like tearing this engine all the way down and I have a line on another running 30 engine.

If the replacement cap is machined to a different place than the original the crank may not turn, .001 will make a big difference.
Tony

I hear ya. I'll spend some time shimming and measuring and trying to ensure clearances. If this is an excessive in futility and I'm out $100 bucks and a couple of hours that's ok. The car isn't drivable now and if it's not after I throw this cap on I'm not really losing much. If it gets me on the road for even a hundred miles that's cool also. I don't plan on this being a long term fix if it works, just something to have a little fun before I start tearing things apart.

Today I measured my replacement cap clearance. I can't find a specific clearance spec for a 194 but I did find one for a 35 207 at .001" - .003". I finally got some plastigauge in and with no shims I'm sitting right around .0025, a bit between .002 and .003. I measured 4 times around the crank, rotating it about a quarter turn between measurements. It was hard to get a good picture, but I think you can make this one out.




I also ordered a new front motor plate since mine is bent, hopefully in this week.

Based on my experience with plastigauge the gap is on the wider side of acceptable. I have found that the plasigauge and babbitt both being somewhat flexible underestimate the gaps.

You can carefully file a little off the cap to tighten up the clearance a bit.
Use the widest file you can find.
Clamp the cap securely while filing, and try to file the same amount evenly across the flat face of the cap.
Make sure to clean the cap well and reinstall.
If you can turn the crank freely after the cap is tightened on, you are NOT too tight.
Continue until you can feel a slight drag when the cap is tightened on, then add just enough shims for the crankshaft to turn free.

I thought your front plate might be bent.
Thought that was the most likely cause of the broken cap.
Check your rear mounts.

I concur with Chipper, plastigage used with the babbitt bearings is only an indicator of the clearance, not a solid number to rely on.

When I rebuilt the '28 engine in my one ton truck (Lurch), I needed to take a little material off the middle bearing cap in order to close the gap on the crank.

I did not use a file. Instead, I flat sanded it, putting a sheet of 400 grit emery cloth on a flat steel plate and carefully sanding the bolt flanges down a little.

I think this procedure is safer than using a file where you can easily take off too much material and end up with the flanges not perpendicular to the bolt holes.

Here's the post that describes what I did, along with a few pics: Flat sanding a '28 middle main bearing cap

Cheers, Dean

When doing any "facing" like that I prefer to use a piece of window glass as a backing for the emery paper that is larger than the job so that all of the surface has contact with the emery. Unless the steel plate is machined flat the glass is generally flatter.
Tony

Thanks, fellas, I have a surface ground plate from my time on the race team I use to lap or face things on. I think I'll give it a go with some emery paper and try to tighten up that clearance a bit. I wonder if the old Model "T" newspaper trick for rod bearing clearance is worth trying since the plastiguage seems to not be as accurate as it could be.

The "spin" test (or "drag" test) is the most accurate and was what Chevrolet recommended.

I hear ya, I just don't have any shims or shim stock and I'm trying hard not to be impatient. I can't seem to find front shims available anywhere online so I guess I need to order some shim stock and make some. I'll wait and do it the right way.

Hi again,

I made some bearing cap shims when I did my '28 engine rebuild. Here's a link to that part of the story, along with a photo or two showing the shims: Making shims and setting main bearing gaps

I should note that my initial setting of the gaps was erroneous. Towards the end of the build, when I got the engine started, it had a couple of soft engine knocks: one in the center main bearing and one in the front main bearing.

I removed shims that I had put in previously and got the knocks to go away. ;-) You'll find this part of the story towards the end of the whole thread.

Cheers, Dean

You are right!
I can't find shims either.
I didn't think they would be that hard to find.
I even searched for the part number, which is Chevrolet part #362997.

I believe the shims were originally .002" thick, so I would try to get that thickness in brass.
Best of luck! :-)

My shim material came in today. So I ran home to play with the car during lunch. I had "faced" the cap since my last post, to the point where the crank was just dragging. I didn't want to take too much off and ruin the cap. I quickly cut some shim stock to a template I made off of the cap. Slapped it together and it spun free. For fun, I tried a bit of plastic gauge again. This time, with a shim, it came out right at .0015 with the crank supported.

My new motor plate is still due tomorrow. I don't know if the existing one was bent by impact or if someone installed the engine incorrectly. I don't know if its necessary but I thought I would loosen all the motor mount bolts, support the engine, remove the bent plate, then reassemble. I want to make sure no undue sideloads are put on the plate again.

-Primo

My new motor plate arrived, after a bit of searching around I realized pulling the front plate isn't that straightforward. My manual was lacking in directions to pull the camshaft so I followed the directions from this post: Camshaft removal. I notice he says check you manual on how to pull the front plate. This is also not in my manual, is there a process other than supporting the engine and loosening the bolts?

So I have the car mostly back together. I tried to get it to fire real quick so I can tune, it was running fine before teardown. It was just puking oil everywhere. I set the timing to to 12 deg btdc, gapped my plugs to 40 and checked valve clearances, I know cold but a couple got bumped. Every once in a while it barely stumbles but won't fire, even with either. I pulled the timing cover to double check I had it lined up. I also checked spark to all 6 cylinders, good there. I'm stumped for tonight.

Probably a silly question,
and don't want to sound insulting, but

Are you sure you were on TDC of #1 and not #6 (1 turn out) when you installed the distributor?

Just seems strange that you wouldn't get anything, even with a shot of ether.

Yeah I was watching the rockers on 1 while rotating the engine over. Watched intake come up then centered the pointer in the 1|2. Just double checking, cylinder 1 is closest to the radiator right?

I really hope it's something boneheaded like that on my part.

To find TDC on #1, which is closest to the radiator, on the right revolution of the crank,
watch the rockers on #6 (six), which is closest to the firewall.

Turn clockwise (viewed from the front) until the exhaust valve on #6 has just closed and the intake has just barely started to open.
Watch the timing pointer at the same time for the marks on the flywheel.
You will now be at TDC on #1, on the right revolution to install the distributor with the rotor pointing to the #1 tower on the distributor cap.

Hope that gets you going! :-)

Yay bonehead mistake!

Runs now, thanks man!