VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1912-1928 28 engine rebuild

Hello,
Has anyone rebuilt their engine on their own? Would anyone recommend this?
I am planning on doing mine but would really appreciate some guidance. Thanks for any tips, advice, and recommendations.
Jim Crowell

Hang in there and I am sure one of the 4 cyl Guru's will be along as there is lots of expertise available here . In the meantime search the 1912-1928 Forum. Lots of info. Go to the Forum "Tech Talk " and check out the School is in Session article by Antique Mechanic. I think it will answer your question.

Hi Jim,

Welcome to the VCCA forums! You'll find lots of great info and people here. ;-)

The answer to your question is yes! There are a couple of play-by-play documented builds on this site.

Ray Holland (aka AntiqueMechanic), a master mechanic, rebuilt a '28 Chevy engine in a series called School is in Session. This story resides in a 250 page PDF on our web page of Technical Articles. To access this list, however, you need to be a member of the VCCA. There are MANY good reasons to join, like getting access to technical experts, being able to post photos on the VCCA website and many more.

Four years ago, I rebuilt the '28 engine in Lurch, my 1927 one ton truck (see the links below). I documented that journey here: Resurrecting a '28 4 banger

Keep us posted about your adventure!

Cheers, Dean

Hi Dean,
Thanks for the information. However, I think there is a problem. I am a member, and as far as I know, I am logged into the forum but still can not get access to the members only section. Would you be able to help me out with that?

Hi again Jim,

I see that you've got your VCCA number in your profile. Cool!

One of the forum admin. folks need to authorize your username for the club privileges. Unfortunately, this is a manual process. ;-(

I'll send one of them a message to get the ball rolling. Hang in there!

Dean

Thanks Dean,
I’ve been looking through the link you sent me. It’s going to be very helpful. I already feel more confident about starting this project.
Jim

Jim,
I am one of the "elves". I verified your VCCA membership and have the honor to be able to change your status on Chatter to VCCA member. You now qualify to see threads and forums reserved for VCCA members. Some privileges are reserved for VCCA members. We hope that it is one of many benefits of VCCA membership and an incentive for some to join us as dues paying members.

If you have bearing inserts then do it yourself. If you have poured babbit bearings for your mains and rods then you might want to have a pro do the rebuild. I had mine rebuilt with new babbit and align bored crank bearings. It was very expensive but if you don't have the tools and old time knowledge then you have to pay someone to do it for you. I'm very happy with how it turned out.

I am slowly rebuilding a '28 motor currently -it's only slow as all sorts of other life and workshop stuff keeps getting in the way.

These motors really are quite straightforward to work on. As said, the big end and main bearings in these motors are white metal Babbit lined. If it's necessary to renew these it does require some specialist knowledge and equipment. But there are companies who can do this work for you.

Indeed, life gets in the way. I haven’t been able to work on my car for some time now. But with all the advice and links I have been given here, I am feeling confident and eager to get started on the engine tear down. Thanks for your response.
Jim

It has begun! I got a good start on the engine tear down today.

Looks nice and clean in there. The first of much good news, I hope.

Mike

Does anyone know how to test the oil pump to see if it is in working condition? I would like to save the $300, and use the pump that is already with the engine.
Jim

Hi Jim,

There's not much to these little vane pumps so you should be able to salvage it. I recommend taking it apart and cleaning it up first. Check to see how much slop there is between the shaft/rotor bearings and the case. If it's really sloppy like mine was, I would take it down and have it bored out and bushed by a machine shop. The next thing to check is the small spring between the vanes pushing them outwards to contact the case. As cheap insurance, replace this little spring even if it's still intact (they're often broken or even missing). I would double check your dimensions but I believe this is the replacement spring I bought: https://www.mcmaster.com/9657K266/.

After that, there's really nothing else to go wrong with it. The only other thing I can think of is the rotor to case clearance though I personally don't think this is worth worrying about too much. The spec is 0.004", mine is more than 0.030" and it still pumps just fine.

Take a pan head screwdriver that fits nicely in the pump shaft slot, cut it off and put it in a drill to drive the pump (clockwise when looking down at the top of the shaft). Stick the pickup in a couple inches of oil and let it rip, as long as it appears that you visually have good flow, you should be in good shape. Once you have the engine all put back together, you can use the screwdriver and drill to prime the oil ways before you install the distributor and fire it up. For reference, my pump puts out ~12 PSI when the oil is cold and drops down to ~8 PSI when the oil gets up to operating temperature (SAE 30) and cruising speed. At idle, it will drop down to 4 or 5 PSI after the engine is warmed up. I'm sure if the rotor/case clearance was tighter, the pump would put out slightly higher pressures however, as long as it registers more than a couple PSI, you should be good to go.

-Tyler

Tyler,
Thanks for the input. I will check all those things. I will post a picture once I’m done.
Jim

Hey buddy, I will swap ya' LOL. Look close, that is a 28 171 under that mouse house. Sucker is still froze but we found Jimmy Hoffa. Yours looks new compared to this thing. The only good news is the engine number matches the title. I will sleeve it if I have to since it is already 40 over. Phish

Phish,
If you ever hear me complaining that my project is not going well, be sure to repost these pictures again. Haha. The person I bought the car off of had been through the engine once before. However, I could get it to turn by hand. I thought it best to tear it open and see what the problem is. Glad I did. None of the bolts were torqued down. I’m eager to see what else was done wrong. Good luck on your project. Keep me posted on how it’s going.
Jim

The '28 motor I'm rebuilding is at + 1/16" already; so, 3 3/4" bore. I have a set of Chevrolet 261 truck pistons to use in my rebuild -the 261 bores are 3 3/4" stock, so the +.020 pistons I have will leave the motor at + 0825" bore. It looks like the block will bore to this OK; will obviously pressure test it before building the motor up. I've attached a couple of photos of a sectioned '28 block showing how thick the cylinder walls are -thanks to Herb Kephart for these photos which were posted on another forum.




The 261 pistons have a slightly taller compression height than the stock piston (1/16" from memory) the compression being raised slightly from (IIRC less than 5:1 stock) won't hurt. The pin diameter of the 261 piston is huge, so will need me to fit bushes fitted to use with the rods' small ends.

That is great to know on the block thickness. One junk yard motor shows +.050, spins nice. So touch hone and reassemble as a spare. The other junk yard motor (froze) has rusted cylinders and we had to beat one piston out. It shows +.040 labeled on pistons. It has the matching block # to tiitle so will take it to 60 over. That one is going to J&M in Ma. Thanks for pics.

Picked up a 28 motor today. Scope showed that it had a valve job on head but stock bore original rings etc. Pulled the pistons and found #2 & #4 had a steel snap ring in the bottom of piston. They do not look homemade. Tabs were pointing out on #4 and pointing in of #2. It's like someone tried to add weight? Balance? Anyone see this? Thanks Stephen

Expanders.
Not about weight or balance. All about clearance.
Used to expand out the thrust faces, reduce clearance, take care of piston slap.

It looks like someone misplaced their '25 or earlier tail light lens retainer clip.

So is that an OEM part? The machinest decides who needs it? Will do some measuring today, see what we have. Thanks

Update. found OEM piston skirt expanders on ebay for 8 bucks. Tree is shady.

Piston skirt expanders are an aftermarket item. They were commonly used in the 30s/40s/50s. There are many different types, even for cast iron pistons. They must have helped, but it's hard to imagine how they did.

Mike

I really don't know how they reliably got the amount of expansion, and thus the piston clearance, they wanted. Maybe a variety of different "strengths" to choose from?
Seems it would be more effective with aluminum than with cast iron.

Doug Bell (who apparently was the president of the VCCA in 1961) wrote in his book "The Cast Iron Wonder" that some mechanics used to lightly clamp cast iron Chevrolet pistons in a vise (in line with the wrist pin) and hit the jaw of the vise with a hammer. That would set more "cam" into the piston and take out some of the piston slap. He claimed they could put .004" to .010" more cam in by doing this, but also said you needed to have spare pistons around because they occasionally broke.