sick sy

[chopper mech]

Well I just bought my truck a few weeks ago and havent put it on the road yet because I knew something was wrong. The truck would start breaking up @ 3300 rpm and pop out exhaust @ 3500 rpm. So today I had some time and I pulled the plugs to see what they looked like and figured i'd check the compresion. First off the spark plug boots just feel apart like I aint never seen. Then came the bad news five of the cyl. gave 125 lbs. but #6 only yeilded 95 lbs. with my cheap autozone comp. gauge. I gues im going to hook up a air tank to do a leak down. Any sugestions?

 

[jpalmer]

Re: sick sy

well those wires should deff be replaced leak down is not a bad idea, hope there isnt anything wrong with it, oh plugs and their gaps make a big dif too

 

[WyoSyclone]

Re: sick sy

Trying squirting a bit of oil in the two cylinders that are down, and do another comp check on them. If they improve then it's ring problems, if they don't improve it's top-end problems.

65 is way low.... make sure the throttle body is cracked open when you're doing your comp check.

 

[gkrcr882]

Re: sick sy

Start with a good tune up. Plugs, wires, cap and rotor.

 

[chopper mech]

Re: sick sy

yea, the tune up was getting done for sure. Just one cyl. down from the rest #6. I put NGK ur5's in and set the gap at .030 . One other thing that scared me was when I ran the truck up and down the road for two or three passes it was at night and when I pulled in the yard I raised the hood and the down pipe was glowing as was the hot side of the turbo. That was another reason I wanted to pull the plugs and check. I guesed It was lean but the plugs looked dark brown when they came out. mods that are done to the truck that I notice are.

MSD box with timing retard

ACCEL inj. no clue how many #'s they look like they have green dot on them.

greedy profect A boost control (doesnt have a model # on it so I assume its the A with the small knob in the center)

Chip has a control on the dash that reads 0 to 9 then A to F. No clue what it is its ( pulled the ecm - my eprom is stuck to it and it is stuck to my ecm but it has no name on it)

pillar mounted auto meter gauges boost,oil and temp.

Faze fuel air mix gauge.

My intentions are to bring this truck back to stock and get it right before I do any thing. Im going to shoot some oil in that cyl. If its the heads I gues I might as well put the L35's on.

 

[turbodig]

Re: sick sy

95 isn't terribly bad, but it's not 100% healthy, either. Run a couple cans of top end clean through it, before you change plugs out (the crud will likely gork a plug or two).

Once it's all cleaned out, recheck your compression.

My guess is that the combination of the boost controller, mystery chip, and street gas led to a cracked piston ring land on #6. Could also be a cracked head or valve seat.

 

[chopper mech]

Re: sick sy

Well I just put a little oil in #6 cyl and now it raised it from 95 lbs. to about 105 lbs. wich way should I go heads or motor?

And what about that down pipe and the hot side of the turbo glowing after a few runs up and down my road is that normal? This is the first time for me owning a turbo ride.

 

[WyoSyclone]

Re: sick sy

Well I just put a little oil in #6 cyl and now it raised it from 95 lbs. to about 105 lbs. wich way should I go heads or motor?

And what about that down pipe and the hot side of the turbo glowing after a few runs up and down my road is that normal? This is the first time for me owning a turbo ride.

I haven't looked at mine after running it at night, so am not sure what glows, and how much. Excessive heat in the exhaust is actually caused by the timing being retarded too much... just dumps the heated exhaust gasses out of the exhaust rather than using them to drive the piston down.

Do you have Datamaster, or a way to datalog? Would probably be a good time to invest in that equipment - you'll need it anyway. I'd do as Dig suggested and use the top-end cleaner, do another compression check. If #6 is way down you're probably going to be pulling the head to inspect the piston.... do you know anyone who has a boroscope? Might be possible to look inside the cylinder and inspect for a damaged top ring land.

 

[turbodig]

Re: sick sy

If #6 is way down you're probably going to be pulling the head to inspect the piston.... do you know anyone who has a boroscope? Might be possible to look inside the cylinder and inspect for a damaged top ring land.

It's rarely visible... it cracks the land between the top and second ring. (Basically, where all the pressure is pushing down).

Won't hurt to have a peek in there, though if you have access to one.