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Tech / General EngineIs your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!
Just wondering if the damage to the front of my crank and front-most cam bearing is too far to be put in the engine. any input is appreciated cam bearing (notice chip on the left) crank (just scratches)
Crank snout is press fit, clean it up(don't go nuts), make sure nothing is raised and press the damper on. If it's too loose for press fit, then nope. Your not gonna drive a super charger right?
That cam bearing, well if the rest are fine why not just replace that one? Honestly it's hard to tell from a pic how bad it is. How did the cam bearing surfaces look n feel? I'd not worry bout the chip since it's on the top(prob not even on the bottom) but if there is copper showing(on the bottom of it esp), then nope.
I didn't show the front bearing in this engine but it was deff toast!
The front cam bearing is put in with the oil holes in the wrong place. With the tension of the timing chain and valve springs, the cam will be held firmly against the BOTTOM of the bearing, meaning that ALL the bearing clearance will be at the top; but that's where the hole is.
That motor had oil pressure issues; esp at idle, and esp the #1 main & most esp the #1 rod. I'm guessing that's why you're into it in the 1st place? Spun #1 rod? If you haven't looked at it yet, you need to.
Probably had GREAT timing chain lubrication, however, with the oil hole exposed like that. You can see of course that the cam NEVER TOUCHED the top of the bearing, and the thickness of the buildup of crud there shows how big the clearance gap was. That's where all the oil went instead of to the bearings.
The "chip" in the bearing doesn't matter, it's not a problem. Can't see the bottom of the bearing though, where it wears, so I can't say if it's too worn to use. But with the oil holes all effffed up like that, it needs replaced, regardless.
Put the new one in with the holes at about 4:00 and 7:00, as viewed from the front. Put the other 4 in with the hole at about 5:00.
Another tip/trick is to drill & tap the holes for those 3 small plugs around the cam to ¼" NPT, and use pipe plugs; and drill a hole with about a #70 or so drill in the 2 plugs on the sides, that terminate the lifter passages, for timing chain lube. The factory's original "lube" design was for drainback that spills out of those big holes right above the cam, to drip onto the chain; and spray from the cam & front main bearings. But the holes don't always do much good since oil tends to run toward the back, not the front. So if you reduce the spray from the cam brg so that the bearings get lubed properly, the chain will tend to run dry. Needs a bit of extra help (oil delivery) from a place that won't hurt the bearings.
That thing is NASTY. Needs all the bearings and plugs taken out, and a trip to the quarter (dollar bill? credit card?) car wash in that totally naked state, with acoupla cans of "engine degreaser" (diesel fuel in a spray can) and your set of gun brushes, run through EVERY oil passage, to get all the metal chips out. (After all, the vat doesn't dissolve metal) The 22 and .410 brushes are probably the ones you'll need the most. Might even want to get some 4MA gasket remover and use it to clean all the paint off the outside too. Do it early in the morning on a warm sunny day and let it sit out in the sun to dry, and put some oil or grease on the bores, lifter bores, and main saddles; and prime & paint the outside, and the top of the lifter gallery. (please don't paint it orange) Then when you put the cam bearings and all the plugs back in, don't forget this one.
Without it, ALL the oil will bypass the filter, making it essentially just a tank off to the side that holds an extra useless quart; and dirty oil will be fed to the whole engine.
The marks on the crank look like pecker tracks from some bozo using a pipe wrench to turn the crank while "building" it at some point in its life. Probably needs to be reground anyway; I'd just get another and turn that POS in as a core, if it was me.
Last edited by sofakingdom; 04-29-2023 at 09:48 AM.
The front cam bearing is put in with the oil holes in the wrong place. With the tension of the timing chain and valve springs, the cam will be held firmly against the BOTTOM of the bearing, meaning that ALL the bearing clearance will be at the top; but that's where the hole is.
That motor had oil pressure issues; esp at idle, and esp the #1 main & most esp the #1 rod. I'm guessing that's why you're into it in the 1st place? Spun #1 rod? If you haven't looked at it yet, you need to.
Probably had GREAT timing chain lubrication, however, with the oil hole exposed like that. You can see of course that the cam NEVER TOUCHED the top of the bearing, and the thickness of the buildup of crud there shows how big the clearance gap was. That's where all the oil went instead of to the bearings.
The "chip" in the bearing doesn't matter, it's not a problem. Can't see the bottom of the bearing though, where it wears, so I can't say if it's too worn to use. But with the oil holes all effffed up like that, it needs replaced, regardless.
Put the new one in with the holes at about 4:00 and 7:00, as viewed from the front. Put the other 4 in with the hole at about 5:00.
Another tip/trick is to drill & tap the holes for those 3 small plugs around the cam to ¼" NPT, and use pipe plugs; and drill a hole with about a #70 or so drill in the 2 plugs on the sides, that terminate the lifter passages, for timing chain lube. The factory's original "lube" design was for drainback that spills out of those big holes right above the cam, to drip onto the chain; and spray from the cam & front main bearings. But the holes don't always do much good since oil tends to run toward the back, not the front. So if you reduce the spray from the cam brg so that the bearings get lubed properly, the chain will tend to run dry. Needs a bit of extra help (oil delivery) from a place that won't hurt the bearings.
That thing is NASTY. Needs all the bearings and plugs taken out, and a trip to the quarter (dollar bill? credit card?) car wash in that totally naked state, with acoupla cans of "engine degreaser" (diesel fuel in a spray can) and your set of gun brushes, run through EVERY oil passage, to get all the metal chips out. (After all, the vat doesn't dissolve metal) The 22 and .410 brushes are probably the ones you'll need the most. Might even want to get some 4MA gasket remover and use it to clean all the paint off the outside too. Do it early in the morning on a warm sunny day and let it sit out in the sun to dry, and put some oil or grease on the bores, lifter bores, and main saddles; and prime & paint the outside, and the top of the lifter gallery. (please don't paint it orange) Then when you put the cam bearings and all the plugs back in, don't forget this one.
Without it, ALL the oil will bypass the filter, making it essentially just a tank off to the side that holds an extra useless quart; and dirty oil will be fed to the whole engine.
The marks on the crank look like pecker tracks from some bozo using a pipe wrench to turn the crank while "building" it at some point in its life. Probably needs to be reground anyway; I'd just get another and turn that POS in as a core, if it was me.
Tearing into it mostly to see the health and do some precautionary maintenance which was just going to be rod bearings and an oil pump. Bought the engine for $250 a couple months back. have been considering going a bit further and getting it honed and some new rings put in. Previous owner claimed it ran when it was pulled but thats not really saying much. I haven't gotten the rods undone yet so I dont know if one of them spun
04-28-2023 | 09:35 PM
Probably needs to be reground anyway; I'd just get another and turn that POS in as a core, if it was me. 