Melted Piston Pics from the tow rig
#18
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things brings up a question i've often wondered the correct answer to...
should we be mounting the pyro thermocouple on cyl #6 ??? we all know that cyl #6 runs the hottest (gets the least amount of air)
i have a lot of experience with 1.8t audi/ vw motors and in those cyl #2 runs the leanest and cyl #4 the richest.... many of those guys run the pyro on cyl #2..... and tune it so all the others are running rich (in a gasser rich makes it run cooler)
i'm guessing the main reason we dont mount the pyro on #6 is that it would be a pain to do it wihtout pulling the manifold... i've got 2 spare stocker manifolds and also a spare thermocouple i might have steal my brother guage for a day and run 2 guages with on reading from #6 and one from the collector.... would be a very interesting comparison.
should we be mounting the pyro thermocouple on cyl #6 ??? we all know that cyl #6 runs the hottest (gets the least amount of air)
i have a lot of experience with 1.8t audi/ vw motors and in those cyl #2 runs the leanest and cyl #4 the richest.... many of those guys run the pyro on cyl #2..... and tune it so all the others are running rich (in a gasser rich makes it run cooler)
i'm guessing the main reason we dont mount the pyro on #6 is that it would be a pain to do it wihtout pulling the manifold... i've got 2 spare stocker manifolds and also a spare thermocouple i might have steal my brother guage for a day and run 2 guages with on reading from #6 and one from the collector.... would be a very interesting comparison.
#19
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The timing was higher than we thought we set it at, but only at 26.5 degrees EGTs were not over 1200 at any time, so I know it had to be a pyrometer issue or possible oil cooling jet that was plugged.
I had the timing at 26 degrees with the same pump on my black truck with no similar failure, though I know the EGT's were higher with it compared to the tweaked 180 pump I put back on it.
I had the timing at 26 degrees with the same pump on my black truck with no similar failure, though I know the EGT's were higher with it compared to the tweaked 180 pump I put back on it.
#24
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This happens sometimes, when the stock piston-cooling (plastic) oil jet that squirts oil from underneath, falls out allowing the piston to overheat.
#25
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Just a off beat thought but did you keep track of the injector that came out of that hole? If the cooling jet looks to be in place and not plugged I would be sus/inspecting that shooter.
#26
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They have been marked and will be sent to the manufacturer for inspection before I reinstall them in the rebuilt engine.
#29
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I remember seeing a cummin kit that improves the coolant flow for the rear cylinder. They use it in heavy duty power generator applications. That has to be the worst looking piston that I've ever seen. Now the fun is beggin to happen. You got 300k out of the last motor, a fresh motor with upgraded pistons would also help for those days you need to put the foot thru the floor board. I like your egt probe idea for the rear cylinder, but who looks at there egt gauge anyways. Happy wrenching buddy.
#30
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This engine is out of the tow rig, my 96 truck I picked up in Louisiana last year.
I have the coolant flow improvement kit on my black truck, but we didn't put it on this truck yet. In fact, I was the original poster that brought that kit to the webs attention
It will go on when the engine is re-assembled.
I need to have cold weather starting so I will stick with stock pistons, I'll just have the bottom end balanced and blueprinted while its apart.
It still needs to be a 100% streetable tow rig that will start at 10 degrees, so nothing exotic will be done to it.
I have the coolant flow improvement kit on my black truck, but we didn't put it on this truck yet. In fact, I was the original poster that brought that kit to the webs attention
It will go on when the engine is re-assembled.
I need to have cold weather starting so I will stick with stock pistons, I'll just have the bottom end balanced and blueprinted while its apart.
It still needs to be a 100% streetable tow rig that will start at 10 degrees, so nothing exotic will be done to it.