Wrong injectors = piston damage.

[Blackbumper]

Wrong injectors = piston damage. Update

I took some pics of the cylinders last night to show what wrong injectors can do to the pistons. #3 and #4 show the most damage I am assuming because they run hotter than the outer ones. Anyone know where the best place is to get some new pistons?

 

[Timbeaux]

Wow. what injectors were you running?

 

[RacinDuallie]

For pistons- Cummins direct, Arias, Mahle(cheapies).....

 

[Blackbumper]

Wow. what injectors were you running?

Well the injectors I pulled out were stock but obviously someone had some different ones in there. I bought the truck wrecked and am in the process of rebuilding it so I never had the pleasure of doing the damage myself. I
m guessing after the insurance company totaled it they went and pulled all their aftermarket stuff off the pillar is also missing were they had the gauges and the hole in the exhaust manifold showed that they had a pyro.

 

[Blackbumper]

That's funny just left him a message this afternoon. His kits have the mahle pistons and the guy that builds my gas motors had nothing but good to say about them he uses them in all his spint car motors. But my question do they make a decent diesel piston? I also talked to Harry up north and his prices on pistons seemed pretty good for either the stock or the marine. Whats your opinion on switching to the marine? So yeah I will have my work cut out for me I am hoping to get into the bottom end tonight and find out how much else I will need to replace.

 

[Jim Fulmer]

I run a set of pistons that PDR sells except mine are milled for lower compression and a bigger valve lift. They are perfect with a 155 degree pattern injector (370)

Jim

 

[Blackbumper]

Update on Pistons

Got the pistons out last night and thought I would post the updated pics. Good news is the bearings looked decent on the crank and tolerences were all within spec to use standard sizes including the cylinder taper and out of round. One coment, the haynes book that I got the specs out of were off we realized this after the first 5 measurements came in larger than the specs!

 

[Blackbumper]

Just got back from the machine shop and everything is starting to look good. There are a couple of very small blemish's but nothing from the burnt piston damage. While he was at it he balanced the crank and rod's down to 0 grams and polished up the journals. The only problem was that his guys threatend to quit if he took in another diesel they are used to moveing around chevy small blocks with cranks they can throw around and blocks that one guy can move.

 

[wrongway]

Just got back from the machine shop and everything is starting to look good. There are a couple of very small blemish's but nothing from the burnt piston damage. While he was at it he balanced the crank and rod's down to 0 grams and polished up the journals. The only problem was that his guys threatend to quit if he took in another diesel they are used to moveing around chevy small blocks with cranks they can throw around and blocks that one guy can move.

Damn, I'm jealous!!:hehe: But I am sure happy for you. Keep me posted on how balancing the motor make's it feel. I've thought of doing this also, and any input you would like to share would be great. I am fixing to do exactly what you are doing. Good luck, and keep us posted. Gary

 

[Blackbumper]

It depends on how low you want the compression, I would recommend the 155* bowl regardless. Valve clearance is another issue, you could fly-cut a lower compression piston, or machine for valve clearance on a higher compression piston. For your application I would recommend the second using a Mahle piston, Harry knows about them also.

Well I ended up ordering the mahle 155's from Mark at Piers but after reading this post again are you saying that you have to machine this piston even with a stock cam? I am probably going to be running a Helix 2 but they don't require a flycut on the stock pistons.