LMM: LMM with 222,000 tear down rebuild
- Thread starter malibu795
- Start date
Sorry worried that wrong.. increase overlap will increase bleed off of the dynamic compression.. id like decreased overlap to reduce bleed off
While ive yet to see cam chartsfor both the LBZ and LMM cams the LBZ cam is more responsive, yet "they are the same"
Ive mentioned aftermarket camshaft before in this thread probably some 25 pages ago
Yes, very common to over cam an engine, it's that tq people really love to feel.
Know anybody with a cam doctor?
70k and counting still. Its still runs is just not "right"
TQ is what I need lol plus i cant go too big as im not sending the pistons off for machine work.. so it has to be drop in compatible.
As for the cam Doctor.. no clue.. im sure there is someone around Columbus oh with all the Motorsports that goes on, someone has to have one
Old school way would be plot it out with a degree wheel, graph paper and dial indicator
The lbz cam that came in the junkyard engine in Miami, isnt in good shape. it sat for alot longer than they said it did.
Adam why are you so hung up on/worried about cam selection when you cant even keep an engine in the truck?
Something has to be going wrong here for you to keep ruining them. Whats the common thread with all of the engines? :hmm:
Something has to be going wrong here for you to keep ruining them. Whats the common thread with all of the engines? :hmm:
Who said i ruined camshafts?
For ~20 years ive ran ring gaps at 12/6 o clock to wrist pin.. just couple days ago found out you're not supposed to do that and why. Thanks to Jesse.
Leason learned.
AFAIK this is one of the few times if not the first time ring gap location to wrist pin has been mentioned/talked about.
Ill check the stuff, re ring/light hone it put it back together and go down the road.
And jeese got a couple leads on cam doctor in Dayton area.. they are an old school Chrysler speed shop
For ~20 years ive ran ring gaps at 12/6 o clock to wrist pin.. just couple days ago found out you're not supposed to do that and why. Thanks to Jesse.
Leason learned.
AFAIK this is one of the few times if not the first time ring gap location to wrist pin has been mentioned/talked about.
Ill check the stuff, re ring/light hone it put it back together and go down the road.
And jeese got a couple leads on cam doctor in Dayton area.. they are an old school Chrysler speed shop
I was talking about ruining ENGINES....
How about in the Duramax service/rebuild manual? I usually consult that when Im assembling a Duramax engine.
And if you search, there are plenty of threads on here regarding ring alignment. Im pretty sure Fingers even told you specifically how to align them at one point, if I remember correctly. Id have to search though.
Ring alignment has been discussed in this thread and 180° gaps are mentioned i dont recall any one mentioning gaps related to thrust or wrist pin..untill recently..
Finger and i and others have gone round and round on ring gaps, ptwc and quench
This is the arguably first thing that has gone wrong that can be solely directed at me.
Let's recap the cause of the last 4 engine failures
on an engine that has made at most 413rwhp, spends 98% of its life below 3000rpm with vast majority of that between 18-2400rpm.
The others, split piston, sheared crank dowl pin(at some 245,000 miles), water pump, subsurface crack in main web.
Outside sub surface crack, the other 3 have destroyed engines at random both stock and modified.
Im in no means what soever trying to build a performance engine here.
Does that make me a shitty wrench?!? Apparently you think so.
Finger and i and others have gone round and round on ring gaps, ptwc and quench
This is the arguably first thing that has gone wrong that can be solely directed at me.
Let's recap the cause of the last 4 engine failures
on an engine that has made at most 413rwhp, spends 98% of its life below 3000rpm with vast majority of that between 18-2400rpm.
The others, split piston, sheared crank dowl pin(at some 245,000 miles), water pump, subsurface crack in main web.
Outside sub surface crack, the other 3 have destroyed engines at random both stock and modified.
Im in no means what soever trying to build a performance engine here.
Does that make me a shitty wrench?!? Apparently you think so.
Im just saying, after one engine assembled with pistons backwards/wrong side, and now messed up rings...Im confused why you havent been following the duramax service/assembly manual to a T.
Assembly errors aside, what does your tuning actually look like? Im honestly just curious.
Wow again
Adam something is wrong some way some how. I have hot shot hauler customers that tow heavy and have many many miles on there trucks and not a tenth of your problems. You are a trooper! lol I feel for you every time I read a motor problem post. The one truck 2011 with over 400k just lost a piston. As far as piston rings doing it because of the placement I don't buy it. The rotate all the time. If they didn't you would have problems from carbon. That is what wears out the ring groove.
Adam something is wrong some way some how. I have hot shot hauler customers that tow heavy and have many many miles on there trucks and not a tenth of your problems. You are a trooper! lol I feel for you every time I read a motor problem post. The one truck 2011 with over 400k just lost a piston. As far as piston rings doing it because of the placement I don't buy it. The rotate all the time. If they didn't you would have problems from carbon. That is what wears out the ring groove.
Yes rings rotate, but ever so slightly. Just like a valve. If the ring gap was directly over the thrust surface during break-in, that would be detrimental to ring/cylinder life IMO.
And didn't Adam have trouble getting the rings to seat this last go-round?
And didn't Adam have trouble getting the rings to seat this last go-round?
Rings
If the rings don't seal in the first couple of minutes there not going to seal. If that motor blow oil out like that it had something wrong from the start. That's bad.
If the rings don't seal in the first couple of minutes there not going to seal. If that motor blow oil out like that it had something wrong from the start. That's bad.
X2. It doesn't take 10 000 miles to seat them in a factory engine.
After a couple thousand I would be tearing it down again to see what went sideways.
The 3 times i put an unmolested OEM engine in either of my trucks. It did that for about 10k... explain that
Or explain how every engine whether i assembled or seasoned assembled GM engines uses extre 1-2 gallons of oil the first 10k miles then drops down to 1-1.5 qts per 10k
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Jeff/ Jesse you're both more than welcome to come by tonight/tomorrow as engine should be down to A long/short block tonight
Maybe you have super bum luck with motors? The rings should seat quickly, within a hundred miles, IMO.
When I built my motor, my rings were seated on the first test drive. Didn't even use 1/4 quart of oil for the first change at 800 miles. From then on, it has used about 0.5-0.75 quart per 10k miles. That is with loose rings in my built motor. When it was stock, it would use 0.1 quart per 10k miles, or less. Yes, 1/10th of a quart.
If you're seeing that much oil consumption, something is wrong, IMO. PCV problem, ring problem, etc. You're using more oil than my Dad's Cummins, and it has enough blowby to plug the radiator regularly, and never moves without a trailer behind it (like yours, I suppose).
Edit: OK, I have to ask, though this may derail the thread horribly... What oil are you using during break-in, and then during normal operation?
When I built my motor, my rings were seated on the first test drive. Didn't even use 1/4 quart of oil for the first change at 800 miles. From then on, it has used about 0.5-0.75 quart per 10k miles. That is with loose rings in my built motor. When it was stock, it would use 0.1 quart per 10k miles, or less. Yes, 1/10th of a quart.
If you're seeing that much oil consumption, something is wrong, IMO. PCV problem, ring problem, etc. You're using more oil than my Dad's Cummins, and it has enough blowby to plug the radiator regularly, and never moves without a trailer behind it (like yours, I suppose).
Edit: OK, I have to ask, though this may derail the thread horribly... What oil are you using during break-in, and then during normal operation?
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All OEM assembled engines had over 90,000 miles on them and burnt oil substantially first 10k in use..
Whats the explanation for that?
Whats the explanation for that?