Rebuilding a 141

[matuva]

Will do, though I never did it myself.

May look a dumbass question, but, how can I get sure the new ones fit correctly and won't go out when the block will hold coolant pressure from inside?

 

[3500GMC]

They fit tight. They're easier to install than remove, too.

Use the position of the old ones as a reference. + or - a MM and you are good.

 

[matuva]

IIRC, do exist aluminum rocker arm retainers. Anybody knows where to find them? The stock nylon ones make me nervous when I look at them....

 

[tanman_2006]

I thought the upgrade was brass buttons but either way I'd like to know too.

 

[matuva]

I wouldn't order a single part until you see how your block is going to shape up.

6.5 stock bore is 103mm (4.06inch) First oversize is .25mm if you need to bore the block. I would start with a new 'round' bore, new rings in old egg shaped bores take forever to seat in. Piston slap/wear unseats the ringset on top of that. Blowby out the gazoo...

Top ring is keystone cross section kinda like this, /_\ 3mm thickness Big side, bottom in illustration, toward the piston wall.
Second ring is 2mm thick.
Oil ring is 4mm thick two piece design.

Brand? I like Speed Pro but I'm not sure if they do 6.5 diesel stuff- so probably Perfect Circle would be a good candidate.

I would Definatly re ring it with a hone. I rebuild a 141 and have had no problems yet got 25,000 on it now and driven hard

This is a question that haunts me : re-ring or not, and if re-ring, hone or not (expensive here) How can I check if it needs honing?
May be can I just change the oil ring only?

 

[great white]

If you pull the rings from their bores, you need to at least hone the cylinders so they re-seat properly.

You can measure the rings for their service limit and reinstall them if good (if you want to chance it).

Personally, I'd just throw new rings in rather than the old even if they are in the service limit. With a hone, I prefer to see rings at the installed/new spec since they are going to wear as they seat. Especially with a common rebuilders type honing, the finish is "rougher" than the OEM finish hone.

New engines are very finely finished and so close to running spec when they leave the factory there's very little ring wear as they seat.

The top ring is the one to be concerned with as this is the ring that takes the majority of the compression forces and needs to be run under a load (not a max load though) to seat and not "glaze" the cylinder bores in a diesel application.

You still have to change the oil out (no synthetics on break in please!) at around 500 miles with a re-ring and hone, just like a new or rebuilt engine...

 

[matuva]

Correct me if wrong, honing cylinder walls means "cleaning" them with a kind of "stone-brush tool" or Flex-hone? like this one



Not necessary having to machine it and have to install oversized rings and pistons? Just to get sure, as a frenchie like me can sometimes misunderstand some technical words

 

[matuva]

Going oversized is "boring" an engine, right?

 

[3500GMC]

Oversizing the bore is referred as 'boring' or 'boring out' yes. After the cut (bore) it's then 'honed' to the finished size, texture and angle. (usually 45 degrees)

The hone in the right side pic is very effective for a 'used' block. Sometimes called a dingle-ball hone, or Flex hone.

I wouldn't reuse rings. Once they leave their spot in their respective bore, they'll never seal properly again.

 

[matuva]

Woo woo !! Thanks 3500GMC, I just realise I was in fact making confusion between boring and honing

Boring is very expensive here. So, if changing rings needs honing only (as ong as walls are not too egg shaped of course), I will definately
hone and re-ring

 

[3500GMC]

You should be fine. In extreme cases your block will have a 'ridge' at the very top of the bore. There are cutter tools to remove this ridge if needed. Tool is called a ridge-reamer..

 

[ak diesel driver]

don't hone any more than you have to to clean them up. other wise your removing cylinder wall metal that should be kept to keep clearances

 

[matuva]

You should be fine. In extreme cases your block will have a 'ridge' at the very top of the bore. There are cutter tools to remove this ridge if needed. Tool is called a ridge-reamer..

don't hone any more than you have to to clean them up. other wise your removing cylinder wall metal that should be kept to keep clearances

Will do

About pistons, how do you detect a worn piston pin? Should I have to worry about or is it something which "never" get worn?

 

[ak diesel driver]

check them with a micrometer also the ring lands wil wear

 

[3500GMC]

If anything the bushing in the rod will show wear. The top ring has a steel land to ride on (cast in the piston) so usually the ring takes the abuse. But you should check 'em..

 

[matuva]

I was wondering if it's worth changing the roller lifters too.

Also, are all camshafts the same, or does it exist some torque enclined?

 

[matuva]

what do you think of this kit : http://www.ebay.com/itm/Chevy-BBC-3...Parts_Accessories&hash=item46017c5c5b&vxp=mtr

 

[Twisted Steel Performance]

what do you think of this kit : http://www.ebay.com/itm/Chevy-BBC-3...Parts_Accessories&hash=item46017c5c5b&vxp=mtr

NO.... that is NOT for our motor, our motor uses roller lifters, out cam & lifters are only for our motors, search for 6.2/6.5 diesel if you are looking for cam or lifters.....

 

[3500GMC]

I was wondering if it's worth changing the roller lifters too.

Also, are all camshafts the same, or does it exist some torque enclined?

To my knowledge all 6.5T cams are the same. You can successfully use new roller lifters with the old cam- if the cam is not hurt, of course

 

[matuva]

Would you install new lifters? I mean, is it worth it, or the old ones should be fine?
Are lifters parts that should be replaced in a rebuild process?