Can this engine be repaired?

[Synchro909]

Originally Posted by hardtimes

Well, so much for 'well restored engine', eh !
Did you ever get a chance to talk to seller and happen to ask , about who did the engine work on this engine ?

It's not all that unusual for the clip retaining the gudgeon pin to come out. I suspect some pistons are not dome properly by the manufacturers. The problem may not be with the person who rebuilt the engine, rather the quality of the parts supplied to him.

[mcorrell]

I would tear the engine down and check it out for other issues. based on the grooves in the #3 bore and the poor hone job I suspect there may be other issues. If the only problems found are the grooves and the cross hatch, I would sleeve #3 and bore/hone all bores to the next larger size to clean the bores up properly. Here in the USA the cost would be only about $400-500

[George Miller]

If you have a twist or a bent rod it can cause the clips to come out. It will force the wrist pin over against the retaining pin until it forces it out.
You will not see the twist or bend with your eye you need to check it with a rod checker made for the job. Ever piston rod assembly should be checked when you build a engine.

[nuwala]

Thanks, really appreciate your help.
The only solution seems to be the sleeve after talking to several restoration workshops today, cost are in the range of 400$. I've had the hope that welding would close the grooves, but welded steel is harder than the engine block and can't be honed.
Let me take the engine apart and let's hope there are no further surprises

[40 Deluxe]

Those grooves stop low enough in the cylinder that compression won't be affected much at all. The engine makes most of it's compression in upper part of the cylinder anyway. It may allow some oil usage, but in the real world I've seen a lot of engines run just fine for a long time that way. Now, perfectionists, engineers, machinists and OCD people will obsess over these grooves and lose a good deal of sleep!

[Tom Wesenberg]

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I wouldn't run that engine as is. With the grooves at .040" deep, that means it would take at least .080" oversize to get rid of them. Measure the bore and add .080" to see what size you end up with. I'd bore to the oversize and buy new pistons and rings, or sleeve that cylinder if the rest of the engine is OK.

I would never install valve seats unless it was really needed to repair a crack or recessed seats.

The rough hone and no crosshatch makes me wonder about the babbit and rest of the engine work. I'd take it all apart and check everything. Maybe the valve contact is 1/4" wide and other such faults.

[Kohnke Rebabbitting]

Besides what George said about Rod alignment taking the snap rings out, is putting the open end of the snap ring side ways.

The open end should be either up, or down.

Herm.

[40 Deluxe]

Herm, I was taught the same thing about snap rings over 50 years ago, but I've always wondered if this is just another "old mechanic's tale". I can't envision Model A piston speed ever being high enough for inertia to overcome the light weight of a circlip. I'm more inclined to blame Harry Hammerhand for overstressing or distorting the clip by over squeezing, or reusing one where the pin has worn a notch.

[dumb person]

Check pin, ignore scratches until oil use is a problem,then sleeve only 1 cylinder. Less worry, better smilespergallon.

[Tom Wesenberg]

I've always put the retainer ring gap down, but have also wondered at just what speed the piston would have to reverse to collapse the ring. I just can't imagine any car engine having the rings collapse. I did buy an engine at Iola that seemed to be a perfect running engine, but when I removed the head I found all 4 cylinders had deep wrist pin damage due to missing retainers.

[nuwala]

I've dismantled the "well restored" engine today as preparation for sleeving.
I found some cracks in the lower babbits - how bad is this, shall this be repaired? How can this be repaired, soldering?

[AlanD]

Dumb question - What creates crosshatch, moving in and out as the hone spins?

[Fullraceflathead]

I don't think they look that bad. If the clearance is good I'd run them.

[DJ S]

Not the best Babbitt job I've ever seen but as stated above, I would just run them.

[James Rogers]

Really strange that both caps have different grooving techniques. Almost looks like they were from different engines and fitted to this one.

[Tom Wesenberg]

Originally Posted by AlanD

Dumb question - What creates crosshatch, moving in and out as the hone spins?

Yes, moving the hone up and down at the correct rate to correspond with RPM of the hone will give a nice crosshatch pattern. Doing it freehand you have to be careful to not go so low that the hone stone hits the bearing saddle, or it will ruin the hone or chip the stone.

[Kohnke Rebabbitting]

Originally Posted by 40 Deluxe

Herm, I was taught the same thing about snap rings over 50 years ago, but I've always wondered if this is just another "old mechanic's tale". I can't envision Model A piston speed ever being high enough for inertia to overcome the light weight of a circlip. I'm more inclined to blame Harry Hammerhand for overstressing or distorting the clip by over squeezing, or reusing one where the pin has worn a notch.

No, Mr. 40 I have seen this many times, I think that any engine machine shop can tell you this also.

Thank's,

Herm.

[Kohnke Rebabbitting]

The babbitt is not Ford factory.

Herm.

[nuwala]

Thanks guys. Will keep the babbits.

Looks like I've found the cause of the grooves in the cylinder. I could move the piston pin of #3 out of the piston by just pressing the thumb against the piston pin. #3 is the cylinder with the grooves.

However, I don't understand the way the piston pin shall be fixed in the position. There is no space for any piston pin retainers? The piston pins are as wide as the pistons - where shall the retainers be placed? - see pictures from left and right side of pistion #3 - All the same with the other pistons - there is no space for an retainers. The only difference is that the #3 rod is tight on piston pin #3 with remarkable friction. The other rods move without friction on the pins, but also can be pushed out of the pistons with just a little pressure....

best regards from Germany

[Fullraceflathead]

I think those factory pistons are for the Pins that locked into the center of the piston Pin Bushing area in the Rods.