No compression on three cylinders - 3000GT/Stealth International Message Center

92-Stealth-Twin · 04-13-2008, 07:55 AM

Hey guys i need a little help, i had a NA to TT come in and it was a no start. The guy who owned it said he thought it slipped timing, so i started there i pulled the timing covers and then i pull the spark plugs and pushed the motor through by hand until i got all the marks lined up, and they did. so then i did a compression test cylinder 1 was 0, cylinder 2 was 135, cylinder 3 was 0, cylinder 4 was 35, cylinder 5 was 0, and cylinder 6 was around 75. Then i started to look around and i found that there was some metal in the lower intake plenium, i tryed to use a magnet to get it but it wouldn't pick it up so that lead me to believe that it was aluminum. After that i drained the oil and i didn't really see any metal flakes in it. Does anyone have any ideas? I am going to pull the oil pan off today to see if i can see anything better. I was just curious if anyone had this happen to them. Thanks

defgh1 · 04-13-2008, 09:14 AM

Sounds like you either have broken pistons or bent valves. Do a leak down test to try and isolate the problem.

Doug H

Hannibalzero · 04-13-2008, 09:58 AM

From the compression test results, I think its pretty clear that the front valves are toast. The rears have damage too. The heads will have to come off and be rebuilt. You'll have to wait to see if there was any piston damage, and go from there.

Since you don't know the history of the car, you may want to just pull the motor, and thoroughly inspect the lower end while you are pulling the heads. You could use the oportunity to inspect/replace the oil pump, main seal, and rodbearings.

Joel_CA · 04-13-2008, 09:59 AM

You might see something nasty looking if you look down the sparkplug tubes with a boroscope. Good luck with that.

JJ

92-Stealth-Twin · 04-13-2008, 06:52 PM

okay well, i dropped the pan. there was pieces of the piston skurts in the pan. so then i pulled a rod cap and looked at the bearing and it is scored and i can see brass, but the crank isn't badly scored, just a little but... thats what i have so far...

defgh1 · 04-13-2008, 08:10 PM

Quote:

Originally Posted by 92-Stealth-Twin

okay well, i dropped the pan. there was pieces of the piston skurts in the pan. so then i pulled a rod cap and looked at the bearing and it is scored and i can see brass, but the crank isn't badly scored, just a little but... thats what i have so far...

At this point I would pull the motor. You are going to need a complete rebuild.

Doug H

Hannibalzero · 04-14-2008, 06:17 AM

Quote:

Originally Posted by defgh1

At this point I would pull the motor. You are going to need a complete rebuild.

Doug H

The scored bearing might not be a huge problem if the crank is undammaged. The bearings would obviously need replacing though.

As for the metal (piston?) in the pan, it is conceivable that this is just casting fragments that have broken free. Given the damage to the valves, I'd say that is highly unlikely though. Your valves probably took a chunk out of one or more of your pistons. At this point, I think your best bet is to break the engine down, throroughly inspect all of the damage, and probably do a complete rebuild. Sorry for the bad news.

92-Stealth-Twin · 04-17-2008, 06:44 AM

Its not my car, its a customers car. He doesn't have the money to rebuild it so he's getting another engine for it. once it is out though i am going to break it down a take a good look at it because i want to know what happened. Thanks for the help guys.

04-13-2008, 07:55 AM	#1 (permalink)
92-Stealth-Twin Forum Member Join Date: Aug 2004 Location: Vermont Drives: 06 Evo MR, 96 Talon Trader Rating: (15)	No compression on three cylinders Hey guys i need a little help, i had a NA to TT come in and it was a no start. The guy who owned it said he thought it slipped timing, so i started there i pulled the timing covers and then i pull the spark plugs and pushed the motor through by hand until i got all the marks lined up, and they did. so then i did a compression test cylinder 1 was 0, cylinder 2 was 135, cylinder 3 was 0, cylinder 4 was 35, cylinder 5 was 0, and cylinder 6 was around 75. Then i started to look around and i found that there was some metal in the lower intake plenium, i tryed to use a magnet to get it but it wouldn't pick it up so that lead me to believe that it was aluminum. After that i drained the oil and i didn't really see any metal flakes in it. Does anyone have any ideas? I am going to pull the oil pan off today to see if i can see anything better. I was just curious if anyone had this happen to them. Thanks __________________ 06 Mitsubishi Evo IX MR Edition w/Pioneer Avic-N3 Navigation, Pioneer Ipod Adaptor, 4g Ipod Mini, Pioneer 4-way 6 1/4" Rear Speakers. 92 Dodge Stealth R/T Twin Turbo 96 Eagle Talon TSi w/PTE 60-1 Duel Ball Bearing Turbo, Magnus Intake Manifold, 60mm Throttle Body, NX Direct Port, Coil On Plug, Custom FMIC, ARP Headstuds, Mitsubishi Metal Head Gasket, HKS Kevlar Timing Belt, Eagle H-Beam Rods, Wiseco (.20) 8.3:1 Pistons, Manley Valve Springs and Retainers, Manley Valves, Ferrea Valve Stem Seals, XTD Stage 3 Racing Cluch, XTD Lightweight Flywheel, Bomz Air Intake, Greddy Type S BOV, AEM EMS, Greddy Turbo Timer, PTE 880cc Injectors, Walbro 255lph Fuel Pump, Hayame Cam Gears, Comp Cams 100, Xtune Downpipe, Xtune Cat-Back Exhaust System, Ported Evo 3 o2 Housing, Slowboy Racing Oil Feed Line, Slowboy Racing Manifold, Greddy (style) 38mm External Wastegate, Slowboy Racing Balance Shaft Eliminator Kit, Prothane Motor Mounts, Powder Coated Valve Cover, Halo Headlights, Euro Clear side markers, Lightning Audio 6 1/4" Front speakers, Lightning Audio 6x9" Rear Speakers, Pioneer DEH-P7700MP Head Unit, MaxSpeed Coil Overs, KYB Gas Struts. 92 Dodge Stealth Twin Turbo (sold) 94 Mitsubishi 3000GT (sold) 78 Porsche 928 (sold)

04-13-2008, 09:14 AM	#2 (permalink)
defgh1 Member #0711 Join Date: Mar 2002 Location: Dunnellon, FL Drives: 99 VR4, 04Volvo V70R Trader Rating: (7)	Re: No compression on three cylinders Sounds like you either have broken pistons or bent valves. Do a leak down test to try and isolate the problem. Doug H __________________ 91 Sandstorm TT, 431 AWHP, 433 ft-lbs. , Kormex 25 spline,LSD, RPS CC Clutch, 4 bolt conversion, Super 15Gs, Stage 3 heads, DSM Sidemounts, PST Driveshaft, Blitz DSBS, HKS Exhaust, 3SX Downpipe, Supra Pump, 780 cc PTE Injectors, SX Fuel reg. & dual feed, AEM, Duel WJO Wideband, HKS DL1, Alcohol Injection. Photos: -->

04-13-2008, 09:58 AM	#3 (permalink)
Hannibalzero H to the izzO Join Date: Jan 2003 Location: Northern VA Drives: Recklessly Trader Rating: (53)	Re: No compression on three cylinders From the compression test results, I think its pretty clear that the front valves are toast. The rears have damage too. The heads will have to come off and be rebuilt. You'll have to wait to see if there was any piston damage, and go from there. Since you don't know the history of the car, you may want to just pull the motor, and thoroughly inspect the lower end while you are pulling the heads. You could use the oportunity to inspect/replace the oil pump, main seal, and rodbearings. __________________

04-13-2008, 09:59 AM	#4 (permalink)
Joel_CA Mitsubishi Junkie Join Date: Dec 2005 Location: NorCal / Sac Drives: 2 Pearly Whites Trader Rating: (1)	Re: No compression on three cylinders You might see something nasty looking if you look down the sparkplug tubes with a boroscope. Good luck with that. JJ __________________ 1992 3000GT VR4 (tastefully modified) & 1996 STEALTH RT/TT #47 (restoration work in progress)

04-13-2008, 06:52 PM	#5 (permalink)
92-Stealth-Twin Forum Member Join Date: Aug 2004 Location: Vermont Drives: 06 Evo MR, 96 Talon Trader Rating: (15)	Re: No compression on three cylinders okay well, i dropped the pan. there was pieces of the piston skurts in the pan. so then i pulled a rod cap and looked at the bearing and it is scored and i can see brass, but the crank isn't badly scored, just a little but... thats what i have so far...

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04-17-2008, 06:44 AM	#8 (permalink)
92-Stealth-Twin Forum Member Join Date: Aug 2004 Location: Vermont Drives: 06 Evo MR, 96 Talon Trader Rating: (15)	Re: No compression on three cylinders Its not my car, its a customers car. He doesn't have the money to rebuild it so he's getting another engine for it. once it is out though i am going to break it down a take a good look at it because i want to know what happened. Thanks for the help guys.