85 Compression Test Results
#17
Race Director
http://www.blackstone-labs.com/
#18
Three Wheelin'
Join Date: Apr 2010
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Used oil analyses are good. To make it easier to pull a sample, install a Fumoto drain valve. I've got one on my Volvo XC70, and it works like a champ, and is built to outlast any car you install it on.
http://www.qwikvalve.com/home.php
To learn all there is to know about UOA's (and anything else about lubes) check out http://www.bobistheoilguy.com
http://www.qwikvalve.com/home.php
To learn all there is to know about UOA's (and anything else about lubes) check out http://www.bobistheoilguy.com
#19
Shameful Thread Killer
Rennlist Member
Rennlist Member
Almost surely this is a result of surface corrosion in your rad. The corrosion inhibitors in coolant work at temp and with flow. No heat and no flow for a long time will let the oxidation build up the in the rad. You can try a special corrosion inhibitor, but usually, once it's on there, you can't get it off.
#20
Asking for input, ie, normalcy.
Engine was started and run for about 2 minutes this morning, so it didn't even warm up. It was tested about 2 hours later, essentially cold. Ambient is about 75F.
Passenger Bank
1 175 170 (by radiator)
2 180 185
3 165 165
4 165 165
Drivers Bank
5 165 170 (by radiator)
6 175 175
7 165 165
8 170 165
Engine was started and run for about 2 minutes this morning, so it didn't even warm up. It was tested about 2 hours later, essentially cold. Ambient is about 75F.
Passenger Bank
1 175 170 (by radiator)
2 180 185
3 165 165
4 165 165
Drivers Bank
5 165 170 (by radiator)
6 175 175
7 165 165
8 170 165
#21
Rennlist Member
Thread Starter
Just as a followup, the car ran hot at the time.
Why?
Long story short, injectors were partially clogged.
Once replaced it ran cool.
Why?
Long story short, injectors were partially clogged.
Once replaced it ran cool.
#23
Rennlist Member
Wow; I would never had considered this correlation. Why would partially clogged injectors lead to a hotter running condition?
#24
Pro
Hmmmm ... should I, or should I not ... ohh heck:
Plug colors:
- driver's bank - great.
- Passenger bank - ehhh gee Doc ... all looking a bit white for my liking (hot), still showing touches of tan, and no signs of blistering on the ceramic (fatal overheating).
Each bank has a similar spread of compression values.
So my first question is: what is different re combustion process in each bank, for the plugs in each bank to be so uniformly different in color?
I know nothing about fuelling in '85 cars, but at this point nobody has to, because by simple observation of plug colors, it's clear that each bank is experiencing different combustion conditions.
Over to the '85 fuelling experts.
Plug colors:
- driver's bank - great.
- Passenger bank - ehhh gee Doc ... all looking a bit white for my liking (hot), still showing touches of tan, and no signs of blistering on the ceramic (fatal overheating).
Each bank has a similar spread of compression values.
So my first question is: what is different re combustion process in each bank, for the plugs in each bank to be so uniformly different in color?
I know nothing about fuelling in '85 cars, but at this point nobody has to, because by simple observation of plug colors, it's clear that each bank is experiencing different combustion conditions.
Over to the '85 fuelling experts.
Last edited by UpFixenDerPorsche; 10-17-2015 at 08:01 PM.
#25
Three Wheelin'
Chris if you have time, walk us through how you got there, ok edited out as well to be fair.
Last edited by Crumpler; 10-17-2015 at 10:11 PM.
#26
Rennlist Member
Thread Starter
Couple of telltales.
Downpipes were white inside, same if you looked up into the header pipes.
Intermittent oddball power loss and stutter under acceleration, putting foot to the floor would downshift the trans but the car would stutter and shake.
It wasn't getting enough fuel. Running lean, very bad. Very hot.
Everything else possible had been gone-thru at the time. New MAF, wires, caps, computers reviewed by Rich, intake job, fuel pump, strainers, regulator, water pump, timing, Radiator flush, thermostat and seal, all other sensors, really everything.
Changing injectors --- night and day. On first test drive it ran at the first line on the gauge, where the rest of mine run, instead of midgauge or higher where it had been.
Funny thing, car sat for 10 years, very early-on, during 1st posts about the car, Dr Bob advised at the time to service the injectors and I ignored that piece of advice.
Downpipes were white inside, same if you looked up into the header pipes.
Intermittent oddball power loss and stutter under acceleration, putting foot to the floor would downshift the trans but the car would stutter and shake.
It wasn't getting enough fuel. Running lean, very bad. Very hot.
Everything else possible had been gone-thru at the time. New MAF, wires, caps, computers reviewed by Rich, intake job, fuel pump, strainers, regulator, water pump, timing, Radiator flush, thermostat and seal, all other sensors, really everything.
Changing injectors --- night and day. On first test drive it ran at the first line on the gauge, where the rest of mine run, instead of midgauge or higher where it had been.
Funny thing, car sat for 10 years, very early-on, during 1st posts about the car, Dr Bob advised at the time to service the injectors and I ignored that piece of advice.
#27
Three Wheelin'
Couple of telltales.
Downpipes were white inside, same if you looked up into the header pipes.
Intermittent oddball power loss and stutter under acceleration, putting foot to the floor would downshift the trans but the car would stutter and shake.
It wasn't getting enough fuel. Running lean, very bad. Very hot.
Everything else possible had been gone-thru at the time. New MAF, wires, caps, computers reviewed by Rich, intake job, fuel pump, strainers, regulator, water pump, timing, Radiator flush, thermostat and seal, all other sensors, really everything.
Changing injectors --- night and day. On first test drive it ran at the first line on the gauge, where the rest of mine run, instead of midgauge or higher where it had been.
Funny thing, car sat for 10 years, very early-on, during 1st posts about the car, Dr Bob advised at the time to service the injectors and I ignored that piece of advice.
Downpipes were white inside, same if you looked up into the header pipes.
Intermittent oddball power loss and stutter under acceleration, putting foot to the floor would downshift the trans but the car would stutter and shake.
It wasn't getting enough fuel. Running lean, very bad. Very hot.
Everything else possible had been gone-thru at the time. New MAF, wires, caps, computers reviewed by Rich, intake job, fuel pump, strainers, regulator, water pump, timing, Radiator flush, thermostat and seal, all other sensors, really everything.
Changing injectors --- night and day. On first test drive it ran at the first line on the gauge, where the rest of mine run, instead of midgauge or higher where it had been.
Funny thing, car sat for 10 years, very early-on, during 1st posts about the car, Dr Bob advised at the time to service the injectors and I ignored that piece of advice.
Did you use different stock injectors or change to a four hole variant?
Hey BTW, is this the 85 that you were parting out?
#28
Rennlist Member
Thread Starter
Four hole. See Hilton's thread.
Yes, its the one that donated the hatch.
I still have the engine and the majority of the car.
Its a roller still.
Today we put the shell of the 86.5 parts car onto the trailer.
I spent 4 hours removing the perfect battery box and the 5 speed firewall overlay that allow mounting of the clutch cylinder. Couldn't bear to send it to the scrapper without removing those.
Yes, its the one that donated the hatch.
I still have the engine and the majority of the car.
Its a roller still.
Today we put the shell of the 86.5 parts car onto the trailer.
I spent 4 hours removing the perfect battery box and the 5 speed firewall overlay that allow mounting of the clutch cylinder. Couldn't bear to send it to the scrapper without removing those.
#29
Three Wheelin'
Hey I pulled all the hardware and trim off the 85 hatch, but it is still in one piece and the harness is intact I believe.
If the 85 is coming back from the dead, let me know and I can get the hatch back to you. Glad to donate it if you got the need buddy.
If the 85 is coming back from the dead, let me know and I can get the hatch back to you. Glad to donate it if you got the need buddy.