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In need of a rebuild i think, low compression 1 cylinder and excessive leak down


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#1 jisleyjr

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Posted 02 June 2017 - 08:57 AM

Well it's been a good couple years of no issues with my 88 Fiji. With in the last month things went south. One day while running errands i got on it pretty good (2nd gear and 3rd gear pull) and smelt burnt oil quickly after. It would puff blue smoke while shifting, and then it would smoke minutes after starting up (after a block of driving). So i assumed it was turbo seals.

Pulled off the turbo and sure enough oil running into exhaust. Slapped on a spare so i could rebuild this one (td05h/s16g) and smoke was gone. (the spare turbo was a td05 and i only swapped center cartridge because i didn't feel like undoing exhaust, so i had zero boost)

Then i noticed while cranking the engine it seemed loop sided, like low compression in a cylinder (reminded me the last time i blew a head gasket).

During its last week of driving it was smoking between shifts again and i could smell burnt oil. Some times i'd pop the hood to look for anything odd and i'd notice oil on top of oil cap and specks of oil on the radiator hose and other areas would have specks of hole. I was dripping more then normal amounts of oil onto the ground after parking.

One time after a drive i left the engine running and i popped the hood i had signs of oil dripping out the drain side of turbo onto manifold and it was burning and smoking. Also on the oil cap there was so oil and it was bubbling. I pulled off the hose from the back of valve cover and air was flying out. So i think i have some excessive crank pressure.

Then i did a compression test 140 - 125 - 90 - 125, eek. I added oil to the 3rd cylinder and it went to 95.

I picked up a cylinder leakage tester from harbor freight and started with 1st cylinder to set a base line, at tdc on compression stroke i adjusted pressure until it was at the 5% lose range (could hear the air in crank case). Then i moved onto each cylinder's tdc on compression stroke and the 3rd one was at 35% loss and it was louder.

I pulled off the spare turbo i had just installed and oil was leaking out both the exhaust and intake side.

Then i pull the cylinder off hoping that it was still the head gasket. But the head gasket looks fine, no odd areas around cylinder 3 (or the others). I was looking for sign of deformities and/or exhaust gases pushing their ways to a oil drain or bolt hole.

The cylinder walls look good too and there isn't any thing obvious wrong. Looking at the cylinder head i am not seeing anything odd either, it is a mechanical rocker with JVE kit installed. Everything was snug.

So i am under the assumption that i did something to the rings on piston 3 and need to rebuild the engine.

Does anyone have any thoughts? Or suggestions?
1988 Conquest, Fiji with blue/grey cloth interior. Magna MPI/MS2/EDIS-4, D2's, td05h/s16g
1987 Starion, Black Ext and Black Leather, parts car :(
1983 Starion, Black Ext and grey cloth interior, driveway queen
2006 Acura TL, Anthracite Ext with Black Leather, rolling on 18's.





#2 scott87star

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Posted 02 June 2017 - 11:49 AM

Your logic seems sound, time to pull #3 out of the hole.
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#3 jisleyjr

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Posted 19 June 2017 - 09:40 AM

I got the engine out and onto a stand. I pulled out cylinder 3 and if i am not mistaken this is a broken ring land:
https://goo.gl/photo...sVKPEViWhFfc2T8

I have a spare block in the shed from a previous car, i might pull the pistons out of it and if the same size put some new bearings and rings on it and reassemble.

Edited by jisleyjr, 19 June 2017 - 09:42 AM.

1988 Conquest, Fiji with blue/grey cloth interior. Magna MPI/MS2/EDIS-4, D2's, td05h/s16g
1987 Starion, Black Ext and Black Leather, parts car :(
1983 Starion, Black Ext and grey cloth interior, driveway queen
2006 Acura TL, Anthracite Ext with Black Leather, rolling on 18's.

#4 scott87star

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Posted 19 June 2017 - 01:54 PM

That would be a broken ring land.
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ECU Vendor link:  http://www.starquest...howtopic=137426

#5 G54Bstore

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Posted 22 June 2017 - 05:49 PM

Dang that sucks. At least you know what to do to fix her up.
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#6 jisleyjr

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Posted 23 June 2017 - 10:06 AM

Yes it does suck, i would be less annoyed if this happened in the fall. Would be a nice winter project. Now i just need to find the time to work on it.
1988 Conquest, Fiji with blue/grey cloth interior. Magna MPI/MS2/EDIS-4, D2's, td05h/s16g
1987 Starion, Black Ext and Black Leather, parts car :(
1983 Starion, Black Ext and grey cloth interior, driveway queen
2006 Acura TL, Anthracite Ext with Black Leather, rolling on 18's.

#7 jisleyjr

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Posted 18 July 2017 - 01:29 PM

I had some time yesterday to tear into the spare block that i had in the shed. The pistons look different, no markings on the top and when looking at the sides there are these lines (from machining?).
https://photos.app.g...l4rWwHXoaPYuox2
https://photos.app.g...0eXBZGHuR1dYPY2

There are some numbers on the inside: 2725
https://photos.app.g...LmHrswAegCXrgH2
https://photos.app.g...ePywEcqIVLkxYj2

I measured the diameter and it is 3.580". The piston i pulled out with the broken ring land is 3.563"

So i am thinking that the spare block was rebuilt with .020 oversized pistons. Thoughts?
1988 Conquest, Fiji with blue/grey cloth interior. Magna MPI/MS2/EDIS-4, D2's, td05h/s16g
1987 Starion, Black Ext and Black Leather, parts car :(
1983 Starion, Black Ext and grey cloth interior, driveway queen
2006 Acura TL, Anthracite Ext with Black Leather, rolling on 18's.




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