Engine damage question....

[tbirdtbird]

"Agree fully with James Rogers. And we discourage old-school long skirt pistons here and favor the 283-style which I have posted on so many times"

An these are American made. Contact Pete's Auto Machine in NM.

Several threads on this, and Geo Miller has also used them, along with many others

[adavis]

Sorry this took so long. Here is a picture of each of the main bearing caps. The block is at the machine shop so I don't have the ability to get pictures of that half of the bearings. The look fine to me....no ridges that I can feel with my fingernail. No flaking off anywhere. What do you think???

[Kohnke Rebabbitting]

I can only see one picture. Lay the shims off so we can see the part lines also.

Something dosn't look right with the top right hand corner, could be just the picture?

Herm

[adavis]

I'll have to take other pics tonight. Apparently I had my phone set to Hi-Def when I took the pics so they're too large to post on here. I will move the shims as well.....

[George Miller]

Does not look like the crank is making full contact with the bearing to me.

[Kohnke Rebabbitting]

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Like James said, the rods were not tinned right. I do see small deposits of tinning, but with Temp. for tinning and pouring not being right, it will never take any way.

Also the No. 3 picture of a piston would fail any way, even if it looked like new, because the rist pin lock, or snap ring is not put in right, and it don't take long!

My opinion on the pistons is like the other guys, they just were short on clearance.

The scoring always starts above the top ring and works it's way down. Pluging up rings, and scoring the skirts, and move's on to the bearings.

Like James said, better find a New builder, as you can not expect anything different out of that guy.

Herm.

[Kohnke Rebabbitting]

[BlueSunoco]

Good thread! Very interesting, learning a lot here thanks.

Adavis, think of all of the hundreds of Model T's and A's running around that this shop did their creative work on. Yikes

[adavis]

OK, lets see how many of these pictures come through. There ARE differences in the color and gloss of the bearing surfaces, but there is no difference in feel. I can take other specific pictures if it will help. Thanks again for the input. I just don't want (or have the money) to not do this right this time.......

In the pics, the black stuff must be RTV from when they were installed. It looks like the shims were held in place with some light RTV....is that an acceptable way to install them? Also, there are a couple "scratches" in the rear main. They are visible in the pictures. I'm not sure how those happened. I was very careful when removing the cap, but I may have nicked it on something somehow? It appears to be a clean scratch and I don't know how else it could happen at an angle across the bearing surface..... The groove that is almost parallel with the oil groove on the main looks to me like it was intentionally put there when the bearing was made. Almost like he was going to make a second oil groove?? Or maybe he started to make the groove in the wrong place and caught it after he started???

One last thing....the end of the bearings where the mate with the block look good, even though in the pictures it doesn't look that great. I think the black RTV makes it look not so good, but in real life the ends look clean and solid. I can try to take a better pic of that area if it matters.....

[jr-41ford]

Originally Posted by BlueSunoco

Good thread! Very interesting, learning a lot here thanks.

Adavis, think of all of the hundreds of Model T's and A's running around that this shop did their creative work on. Yikes

I agree, very interesting thread.

I know who the builder is and have never heard a bad word about any of this shops engine rebuilds. In fact, several of our club members have had their engines rebuilt by this shop.

All I can say is WOW!

[adavis]

jr-41ford.....I completely understand what you are saying. I'm not blaming anyone because I don't know enough about this stuff to point fingers, but from what I'm learning it doesn't seem good. I'm sure there are a gaggle of engines out there built by this shop, but I have got to figure out why mine isn't right so I can fix it.

[Kohnke Rebabbitting]

I can't really say that the babbitt in the caps looks like it wouldn't work, if it weren't for all that embedded Aluminum in the babbitt.

Like George said from the wear marks, the shaft should show more contact then that. The bearings should have a light scraping, and also to lift some of that Aluminum out of the babbitt.

Time gear clearance should also be checked.

Your rear main cap looks like the cast is broke out where the pipe goes in, and I would also pull the soft plug to see how far the pipe is screwed in!

I can't see any tack welds on the pipe, to hold it, unless there is on the cap side of the pipe.

[adavis]

Funny you should mention the drain pipe.....
I had the shop replace the front rope seal with a new "modern" seal in April when they redid the rod bearings. Well, that lasted about 100 miles before it was puking oil like crazy, so I pulled the pan to replace it with rope seals and guess what I found. A little steel pretzel in the pan. I was what was left of the drain tube....after it had been tossed around by the rods. I called up the shop and he said it seemed loose, but he couldn't turn it out so he figured it would just stay.
I got a new one and installed it with locktite. He said to make sure I could blow through it when it was threaded in all the way. I checked it and it seemed good. That was with the engine/crank in the car.....now that is out I can definitely spot weld the tube.

How would you recommend "scraping" the bearings? With some steel wool or maybe a soft steel brush?

The timing gear is new, but should I go with a billet one? How can I test for timing gear clearance?

Thanks for all the help.....

[Kohnke Rebabbitting]

You can still blow through the tube when the pipe has the oil flow almost shut off.

You have to pull the soft plug to see, and make a open oil passage of 3/8's Diameter.

Weld the pipe in and then clear the hole.

You have to use a babbitt scraping tool, and very sharp.

Time gear clearance is checked with a Dial Indicator. In this case, with crank bolted down, hold the crank and move the cam gear.

[adavis]

I'll check the oil passage after I weld the pipe in.

Oh wow...I just searched "babbitt scraping" and watched a couple youtube videos. I'm pretty sure that's WAY out of my league. What should I do now with these mains? How can I make sure THEY won't fail in a couple thousand miles???? Ugh.

[insomniacshotrods]

Originally Posted by jr-41ford

I agree, very interesting thread.
I know who the builder is and have never heard a bad word about any of this shops engine rebuilds. In fact, several of our club members have had their engines rebuilt by this shop.
All I can say is WOW!

Isnt 7:1 compression too high for a Babbitt engine? Ive always heard not to go over 6:1 unless you put inserts in. Dont know for sure just asking. Good luck.

[hardtimes]

Originally Posted by adavis

I'll check the oil passage after I weld the pipe in.

Oh wow...I just searched "babbitt scraping" and watched a couple youtube videos. I'm pretty sure that's WAY out of my league. What should I do now with these mains? How can I make sure THEY won't fail in a couple thousand miles???? Ugh.

Have you called Joe at Turlock Machine to show pics and / or discuss problems ?
And, looks like you are running 'stock' A ..dip/splash system, eh ?
If that is the case, I'll have to agree with those who question running is at 3100 + ! If full pressure, maybe different animal with sufficient oiling at that rpm.

[Halswell]

Back in the day when I was learning about the Model A ford engine I was taught that one never put oil control rings on to a new bore. A plain cast iron oil ring as Henry used in the factory was correct. I note that your engine has oil control rings those with scrapers and the w shaped bits etc. This seems to be a common practice now as all the ring sets we are getting here (NZ) contain these oil control rings rather than plain cast iron oil rings. Oil control rings should only be used on re ringing jobs on old bores. I saw another thread where the chap had seized rings same problem! The Model A is not an oil burner even when worn. Happy Motoring.

[James Rogers]

One of the reasons your rear main is leaking so badly is the grooves on the front thrust are not cut correctly. These grooves should go all the way to the edge of the thrust, not just part way. The reason the B engine has the groove cut all the way across the thrust is because it has some pressure from the pump, unlike the A which is gravity feed only. An A will leak with just a small amount of excess clearance with just the head pressure from the valve chamber so, a B will almost spew if these grooves are not properly done. I have a factory replacement rear cap I use for a reference that has the grooves as described. I will try to get a picture today and post it this evening. Any of those rear seals that were the end all be all back in the day are less than useless. I just replaced the mains on an A engine that had a rope that had begun to disintegrate and there were lots of fibers in the pump screen. The other problem this motor had was, an excess of RTV sealer all through the bearings and in the pump. I posted those pics earlier last week to show that, when RTV is used it not only squeezes out of the sides, it squeezes into the bearings also. Once it fills the wells, your engine is DOOMED.

[modelAtony]

Originally Posted by insomniacshotrods

Isnt 7:1 compression too high for a Babbitt engine? Ive always heard not to go over 6:1 unless you put inserts in. Dont know for sure just asking. Good luck.

If engine is built correct and driven the proper way with attention to spark control the 7.1 head will be ok. have fun modelAtony tony white Lafayette, LA