Failed piston ring?

Focus said:
Correct me if I am wrong, but wasn't it the exhaust manifold glowing on cylinder #4 ?

That may have been a contributing factor.
Cylinder #1. Good thinking tho.
 
Kooldino said:
I didn't pull the crank out.
You probably should take it out and check those mains or you'll get it back together and have even more problems..

the procedure I listed is the same for checking mains and for checking rods... just in one case you are checking the saddles and the other end you are checking the "big end".

Keep in mind Dana that one single piece of metal of the right size and diam could do all that damage to that one bearing. And when I say size and diam I mean like grain of sand. Once it etches the surface there is more grit, which does more damage which makes more grit... you get the picture...

A motor can NEVER be too clean :)
 
TurfBurn said:
You probably should take it out and check those mains or you'll get it back together and have even more problems..
I'd have to pull the flywheel off for that, wouldn't I?

Keep in mind Dana that one single piece of metal of the right size and diam could do all that damage to that one bearing.
I hear that.

A motor can NEVER be too clean :)
True.dat
 
Yeah you'd haev to pull the flywheel, and the oil pump would have to come off as well, and possibly the water pump, although I think that can stay on... but definitely the flywheel and then the rear seal housing as well. Plus all the mains... it's not as bad as it sounds...

Finding an engine building shop is actually cheaper to do the motor portion than owning the tools to do it properly. Hence I've researched and understand everything that needs to be done, but am not doing portions of it simply because of tools and accuracy that is required.. I'm not going to crack 400 hp with a hack job :)
 
Just got off the phone with Brian Pauter (of Pauter rods)

He gave me some good advice:

1-check the bottom halves of the main by pulling them off one at a time, and then replaing them. That way, I don't have to pull out the crank.

2-to check the clearances on the rod bearings, I can install a rod (without a piston) upside down on the crank and see how well it moves. I guess I could modify it if needed. Speaking of which, if it were too tight, how would I "loosen" it? Sandpaper???
 
TurfBurn said:
Yeah you'd haev to pull the flywheel, and the oil pump would have to come off as well, and possibly the water pump, although I think that can stay on... but definitely the flywheel and then the rear seal housing as well. Plus all the mains... it's not as bad as it sounds...
To pull the flywheel, I'd have to disconnect the tranny. :(
 
you'd have to hand lap the caps.... lapping compound and a good cloth I believe is one method... otherwise very very find sandpaper may be ok... I have NOT lapped anything... so I"d see what Nick or someone says on that.. but that is basically what you'd do.. I'd have a hard time knowing how you'd judge it just off how it moves.

Follow my writeup :) LOL... (for tranny removal)
 
TurfBurn said:
you'd have to hand lap the caps.... lapping compound and a good cloth I believe is one method...
Where could I get lapping compound?

so I"d see what Nick or someone says on that.. but that is basically what you'd do.. I'd have a hard time knowing how you'd judge it just off how it moves.
Well, if it moves freely, it won't be overly tight, right?

Follow my writeup :) LOL... (for tranny removal)
No. I hate you. :mad:

Making me pull my trans. How long would it take me to do at this point?

Even if I did pull the crank, I don't have all these fancy tools you speak of. And I don't know of any engine shops around here that would have the tools.

And really, I just wanna get this thing running already. It's getting EFFING cold to be riding my motorcycle every day.
 
I'll have them in Saturday morning. Bout damn time. You coming over?
 
Kooldino said:
Where could I get lapping compound?


Well, if it moves freely, it won't be overly tight, right?


No. I hate you. :mad:

Making me pull my trans. How long would it take me to do at this point?

Even if I did pull the crank, I don't have all these fancy tools you speak of. And I don't know of any engine shops around here that would have the tools.

And really, I just wanna get this thing running already. It's getting EFFING cold to be riding my motorcycle every day.
dude, pull the crank if you are going to hone at all... and trust me, pulling the tranny with the engine makes it easier, not harder. besides, when you go to re-install it you have to pull the tranny anyways cause you'll never get it stabbed with the tranny in the car.
 
I haven't looked for lapping compound... so that is a good question... any place that carries some range of metal working supplies SHOULD have it... you could use a medium buffing compound... you need like a 280 grit probably.... there's a chance autozone or the like may carry it.

Well if it moves freely you'd hope it isn't too tight, but you could be on the low side... but you could also have too much clearance and then you'll have s*** for oil pressure, too much leakage, and you'll risk damaging bearings again... If you have the cross members off and so forth already.... pull the trans is probably about 2-3 hours... requires a pickle fork and some patience though.... But like Nick said or whomever, you can just pull one or two of the caps (or all of them) and check the half of the shell there... those are the worst for wear anyway... if you have problems there, putting the motor back together won't get you anywhere for long.

Any engine shop will have the tools that I mentioned... they are the basics of engine building...

May be time to find a 500 dollar civic to drive for a while. :) I have a rust 91 blazer that I'm forced into driving while I rebuild :).

Later!

Kooldino said:
Where could I get lapping compound?


Well, if it moves freely, it won't be overly tight, right?


No. I hate you. :mad:

Making me pull my trans. How long would it take me to do at this point?

Even if I did pull the crank, I don't have all these fancy tools you speak of. And I don't know of any engine shops around here that would have the tools.

And really, I just wanna get this thing running already. It's getting EFFING cold to be riding my motorcycle every day.
 
Correct me If I am wrong, but this is the first time I ever hear about lapping journals. This makes no sense at all. There are sophisticated machines made to work cranks and rods and such.

Who knows maybe I missed something somewhere.
 
Focus said:
Correct me If I am wrong, but this is the first time I ever hear about lapping journal. This makes no sense at all. There are sophisticated machines made to work cranks and rods and such.

Who knows maybe I missed something somewhere.
You don't lap the journal [bearing] itself. You lap the caps and main/rod end to finish off the tolerance for clearance. It's the only way to hit within a 10 thousandth of an inch on your clearance that I know of. Most machines can cut within a few ten thousandths but to get down to that 10th my understanding is that it is typically hand lapped to do so. I know that crank grinders and so forth will hit the ten thousandth. I believe the hand lapping of the caps etc is done because of the individual variation of the bearings and trying to nail every clearance dead on for each location.
 
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TurfBurn said:
You don't lap the journal [bearing] itself. You lap the caps and main/rod end to finish off the tolerance for clearance. It's the only way to hit within a 10 thousandth of an inch on your clearance that I know of. Most machines can cut within a few ten thousandths but to get down to that 10th my understanding is that it is typically hand lapped to do so. I know that crank grinders and so forth will hit the ten thousandth. I believe the hand lapping of the caps etc is done because of the individual variation of the bearings and trying to nail every clearance dead on for each location.
Sorry, never heard of this. Possibly in Formula 1 engines, but then I would assume their tolerances are allready within spec.
 
RyanJayG said:
dude, pull the crank if you are going to hone at all... and trust me, pulling the tranny with the engine makes it easier, not harder. besides, when you go to re-install it you have to pull the tranny anyways cause you'll never get it stabbed with the tranny in the car.
Do It this way!

I took out the engine without taking out the tranny, What a b****!

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TurfBurn said:
Yeah you'd haev to pull the flywheel, and the oil pump would have to come off as well, and possibly the water pump, although I think that can stay on... but definitely the flywheel and then the rear seal housing as well. Plus all the mains... it's not as bad as it sounds...

Finding an engine building shop is actually cheaper to do the motor portion than owning the tools to do it properly. Hence I've researched and understand everything that needs to be done, but am not doing portions of it simply because of tools and accuracy that is required.. I'm not going to crack 400 hp with a hack job :)
Agreed, I think I'm over $18,000 Canadian not including the price of the car, so why get cheap now!

mazda%20mp5t%20-%20(2).jpg
 
Focus said:
Sorry, never heard of this. Possibly in Formula 1 engines, but then I would assume their tolerances are allready within spec.
It was a direct recommendation from my engine builder who is doing my block. I asked for a bearing tolerance of 2.2 thousandths on the mains and he said it'd cost a little more as he'd have to hand lap each cap and main to pull the tolerances down exactly to the 10th for me. Said he had done it enough times before. So common for him to do I guess :). He's a great guy and fun to work with. Could just be a builder method, but it is one way to get there to be sure. He's also balancing out each rod assembly and so forth down to less than half a gram. So everything should be pretty spot on.
 
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