Lurid engine pictures

[Sarastro]

If it hasn't been obvious, I got my hands on a 1275 engine and I've been tearing it down. I plan to rebuild it and maybe put it into the bugeye. In any case, it's more of an educational exercise than any particular goal.

I was pleased to see that the camshaft and crankshaft look pretty good. The crank has been reground once, 0.010" undersize. Journal surfaces are smooth as a baby's butt. However, 6 of the 8 tappets look pretty bad, and one bearing is bad. The rest of the bearings are fine, showing virtually no wear, but this one--yikes! Its the top half of the no. 4 rod bearing.

It seems strange that the tappets would wear this way. Scoring I can understand, but pitting? How does that happen? Seems to imply some kind of corrosion rather than wear.

Same for the bearing--why would just one do this, and show deep pitting instead of scoring? Initially defective? I checked the oil passages, and they're quite clean, but I suppose it's possible that there may have been some crud that came out when I took it apart.

Anyway, it's no big deal--bearings and tappets are cheap--but I do wonder what did this, and I'd like to make sure it doesn't happen again.

 

[jlaird]

Could I guess. Pistons because it was run lean with bad timeing for a long while.

Bearing, because there was a bit of stuff under one side of it and it was not fited correctly.

 

[tony barnhill]

Here's one: how long has it been sitting with oil in it? Oil over time turns into a sorta vinegar substance that could do that as well as eat up the cylinders....that its only on the part of the bearing that was worn is because more oil would sit there while the engine was just sitting around.

 

[Sarastro]

Interesting idea! I don't know how long it has been sitting, but it's been a while. Probably a couple years, at least. The oil that I drained out was sludgy and dirty. Oil would drain completely off the tappets in a short time, so they might have corroded from condensed moisture. There was still oil in the bearings, though. I know, dirty oil has products of combustion, which can be acidic, and that's one reason why oil has to be changed.

The journal diameters are correct, within the accuracy of a vernier caliper--within a mil. I checked the clearance of the other three bearings with plastigage--0.0015 to 0.002 mils; I didn't check the bad one, since it seemed pointless once I saw it.

 

[Hap Waldrop]

All that looks like noramal high mileage wear and tear to me, pitted lifter, and copper showing on rod bearings, seen it atleast hundred times before.

Jack, I think you are blinder than even me those are lifters, or as the limeys say , tappets

Reading this a bit more, it obvious that someone been in there before, reground crank, those lifter could be repalcments as well, the standard lifter aoffering by most vendors today are absolutre junk, with Rockwell C rating in the 40s, wehn they need to be in the high 50s to 60. I recommend the following lifters, all of them I have hardness tst samles of and found then to be 56 or above.

Mini Spares/Mini Mania, ligthened lifter, they checked out very well at 57 C rating, Mini mania gets like $79.00 a set for them

APT CF-10, they are a nice chilled iron lifter, David get like about 79.00 for a set of them as well, 57 or so Rcokwell C

APT CF-04, top of the line lifters with oil drain back holes , these lifter check out right at 60 C rating

These are the only lifters I will ever use in any A or B series engine I build, period, anything else is simply rolling the dice.

 

[bugimike]

Jack, I think you are blinder than even me those are lifters, or as the limeys say , tappets

:lol: I'm glad you said something, Hap....I didn't have the heart!! Love Ya Jack :thumbsup:

 

[Mickey Richaud]

Jack, I think you are blinder than even me those are lifters, or as the limeys say , tappets

:lol: I'm glad you said something, Hap....I didn't have the heart!! Love Ya Jack :thumbsup:

NO - they ARE pistons - it's a 12.75!

 

[GeeBee1]

In Jack's defense, he didn't have his glasses on :wink:

Boy I can't believe how blind I have been getting lately.

Hap, thanks again for the great info.

 

[Glen_B]

That tappet pitting is very typical. I've seen some level of that on every engine I've taken apart. Like Hap, it causes me to buy nothing but APT lifters AND to use Rotella T. This is exactly the type of lifter damage that is to be expected with a decrease in ZDDP in modern oil formulations.

Glen Byrns

 

[BuggerAll]

Are the lifters supplied by Kent Cams with their kits any good? Now you've got me worried -

 

[jlaird]

yep, lifters and yes my eyes are not as good as I would wish. However, as lifters that is just standard old age as you all commented.

 

[Hap Waldrop]

Yep, Jack knows I luv him, just poking at him, I catch myself running around the shop never taking off my reading glasses, and now I can't see anything up close without them. Heck, two years ago, I could see like hawk, now more like a bat

 

[jlaird]

Just wait Hap, they will even get worse.

 

[Jim_Gruber]

I just ordered on line product called Cam Shield - ZDDP Additive in a bottle. Something line an ounce per 4 quarts of oil. $19.95 including shipping . Bottle says treats 30 quarts of oil. Don't know if product is any good or not but since I can't find Castrol Classic around here this seemed like next best thing. Info at www.cam-shield.com.

 

[Sarastro]

Pistons, tappets, eh--what's the difference? Aren't they interchangeable anyway?

Seriously--thanks very much all, especially Hap, for the benefits of your experience. If that's the way they wear, so be it--I'm still a little surprised that they pit instead of wearing in striations.

Guess I'll increase the tappet budget for this project!

 

[jlaird]

Standard tappets 130 bucks. Fancy ones more.

 

[RonMacPherson]

For anyone who has any questions on how/why a bearing failure occurred, I strongly recommend researching this site.

https://mahleclevite.com/publications/CL77-3-402.pdf

They do have a little bit of time involved in researching and compiling the info.

 

[Hap Waldrop]

APT CF-04 are like $120.00 a set form APT, he has antother chilled iron lifter that doesn't have the drin back holes like the factory units, they are CF-10 they sell for for $79.00, Mini Mani sell a ligthen lifter, I personally Rcokwell C tesed them at 57, and they sell for $79.00, Newsflash, Moss is the last place you would ever want to buy lifters, they recently stop selling their "standard" lifters, I'm sure because of the rants of folks like me, now they take the standard lifter, and individually test them for hardness, then include a assembly lube, i wouldn't lube a door hinge with much less put in my engines, they don't state their pass/fail Rockwell C numbers, so who the heck knows, then they also off the APT CF-04 lifter for $150, $30 more dollars that David at APT sells them for.

Just call APT or Mini Mania and get lifters from them the tree lifters I listed above, they are good stuff, and I personally tested all of them on the Rcokwell C tester and in motor with great results, and if you're going to use a ssembly lube, get CRC moly lube from NAPA, that red stuff they sell at the part stores is garbage, most of it ends of dripping down into the oil pan before you ever get around to crnaking your engine, that's why I don't use I noticed a puddle of it in the plastic bag I would bag the engine on stand with, it doesn't stay put it drips off, not exactrly what you want in a assembly lube.

 

[Golden_Swan]

Tappets, like many surface hardened items, will pit after long-time usage. This is not due to the surface hardness, but because of the fatigue failure of the underlying metal. For longer lasting components, a deeper hardening is necessary. Surface hardness of course has an effect. Harder surface helps prevent scoring from dirt and other abrasion. But mostly harder surfaces indicate deeper hardening.

Of course the underlying material has to be tough enough to withstand the repeated forces it is exposed to. A crappy material will pit even with good hardening.

It takes more energy to make deeper hardening, and therefore costs more. A larger amount of metal has to be both heated to hardening temperature, and cooled down quickly to the aging temperature. Double depth requires around 4 times the energy.

 

[jlaird]

Good info. thanks.