Mitsubishi 3000GT & Dodge Stealth Forum banner
1 - 20 of 46 Posts

·
vehicular thaumaturgist
Joined
·
8,289 Posts
Discussion Starter · #1 ·
Ok, well I had checked out the oil after running the new short block for 20 minutes and it looked OK. Slightly shimmery and opaque when a couple inches deep, but I didn't think it would be anything out of the ordinary.

I drained the catch pan today and realized that there were a few small slivers of what I know well to be bearing material. I don't think it is possible that it came from my new engine (factory 4-bolt) at all, and I was thorough as all hell in cleaning out the oil cooler & lines (blew the oil out w/ compressed air, filled with brake cleaner, blew that out w/ compressed air). Does the oil go through the filter after it circulates through the cooler? What might be wrong and what can I do about it?

Secondly (and a bit less seriously) I badly cross threaded a large bolt (17mm head) that attaches to a bushing on the rear of the driver's side control arm. This bolt threads into the frame and as far as I can tell, there is no way to replace it. How is one supposed to replace something that is part of the frame?

I also have a problem with a bent bolt at the front. This bolt sticks out of the frame near the left front tow hook and attaches the subframe (front cross reinforcement) via rubber bushings. It is loose in the frame when the crossbar is disconnected but as far as I can see there is no way to remove or replace it. How?

If anyone has answers to these difficult questions, please respond.

-Chris Wood
 

·
Registered
Joined
·
5,706 Posts
The metal material is normal.From every "new or rebuild" I've ever seen That is why I never run the car for more time then it takes to come up to temp.and usually at the same RPM for the entire time.Then I drain the oil which by now should be hot into something clean.I've even used a coffee/paint filter to catch any unwanted material.Of course you only get a small sample of what is comming out.But you can check the drain pan.Then If it looks normal.The oil will look shimmery and there may be some sizable pieces.Don't ask why, but I have had several long mile motors that really spit out frightening amounts of metal on the warm up run.Then change the filter and add new oil and road test it at different RPMs. Never over revving and never let it sit and idle.Just go out and drive 25-50 miles.Drain all the oil again and inspect what you see.It may still be a bit shimmery but it should be relativly clean and shouldn't give you anything out of the ordinary.If the car ever starts to knock.shut it down and flat bed it.Don't drive it one more foot.
For your stripped 17 MM Bolt.You are going to need a way to get a straight shot at it. Remove the part being bolted to it totally and buy a heli-coil kit.The directions are straight forward.But be prepared to be raped.The kits are usually about $50.00. The stud on the front where the urethane bushing is should be removed and you should be able to rethread it with a dye. If you can't get a helicoil kit that big there is a kit I will show you a pic and proper name if you need it.Basically its like a pop rivit gun.Instead you put a nut on the end of this gun.Place it where you want it in the hole and press like a rivit gun.They are special nuts and the backsides splay and will hold into place allowing basically you to rethread without drilling,Tapping, and adding the coil.The heli coil is much stronger though. Good luck, Mike
 

·
Premium Member
Joined
·
3,186 Posts
The shimmery color is often due to the different assembly lubes (or what ever you used to lubricate everything). Keep an eye on it and you should be okay.
 

·
vehicular thaumaturgist
Joined
·
8,289 Posts
Discussion Starter · #5 ·
Thanks for the replies, guys. I really need to take care of the frame/suspension issue, but I've got bigger fish to fry right now.

I drove my car for ~18mi last night and it's definately burning oil. I figure a car being broken in would burn oil (though I don't know how much is "normal"), but there's quite a bit going on here. I know my DP thermal wrap was covered in it, but it's still burning off in large quantities after quite a while of running the car. I don't think it's a HUGE deal, but I will be taking off the DP and running without it to check for leaks around the rear turbo. I'm hoping that if oil is leaking and being burned it's coming from a turbo oil line or something. I will be pissed if it's coming from the turbine section of the rear turbo or the valve stem seals on the rear head.

At any rate, my larger problem right now is that I can't actually tell how the engine is doing. I am using VERY LITTLE throttle for break-in. No boost, <2k most of the time (hard to stay out of the boost higher than that). At this part-throttle running, I can feel the car buck ever so slightly sometimes and it feels as though something is wrong. It's sort of an irreglar skip or unevenness when accelerating. I don't think it is vacuum-related, but not impossible. I'm pretty sure it's running on all cylinders (we disconnected spark on each, one by one and it idled worse each time).

Any guesses?

-Chris Wood
 

·
Senior Member
Joined
·
1,568 Posts
I think you have a problem with your rebuild. I will admit, I have never rebuilt a 3S motor but I have probably built over 20 small block Chevys and a few Ford and Pontiac V8s and I have never seen bits of metal in oil after rebuild. Even using a magnetic drain plug! Also new engine rebuilds should Not be burning oil. I have put together Chevy race motors which had a total break-in of 3 easy 1/4 mile passes then balls to the wall and not seen the engine burning oil!
 

·
Premium Member
Joined
·
3,186 Posts
I thought he said it was burning oil due to an "external" oil leak, as in oil dripping on the down pipe. Not burning oil due to the engine internals.
 

·
Badassical Baddage
Joined
·
6,535 Posts
You might want to run it higher than 2k, btu keep it under 4500 and try not to let it idle for any period of time until you've put a few miles on it (50-100)
 

·
vehicular thaumaturgist
Joined
·
8,289 Posts
Discussion Starter · #10 · (Edited)
I believe I am burning oil as well as leaking it. I did not rebuild the engine, it is a factory-new mitsubishi 4-bolt short block and I was meticulous in installing the heads, etc. I can't imagine having a spark issue - the plugs are new, gapped at .034 I believe, and I tested to see if any cylinder was consistently not running by disconnecting each one and watching for a change in idle. The wires are old and the coils are presumably original - but I can't imagine a problem cropping up suddenly now for no apparent reason.

Any more suggestions?

-Chris Wood
 

·
vehicular thaumaturgist
Joined
·
8,289 Posts
Discussion Starter · #11 ·
TTT
 

·
Badassical Baddage
Joined
·
6,535 Posts
Well, you can always run a compression check on 'em and see what you find. Maybe the manufacturer didn't assemble things properly.

I've always seen metal after rebuilds, but I don't know how much your really talkign about. There was no big shards or anything, it was always just a little bit of shavigns in the bottom of the oil and that was immediatly after the build, we always drained it after running the motor up and down the RPM band (never too high) until it reached operating temps, then dropped all of the oil out and started over.
 

·
vehicular thaumaturgist
Joined
·
8,289 Posts
Discussion Starter · #13 ·
There wasn't much metal at all, I was just concerned that there was SOME.

I will run a compression test (need to buy a tester), but I'm going to guess the manufacturer didn't screw anything up.

I'm inclined to think that the engine running poorly is related to something outside the engine (though it would be a strange coincidence). I can't figure out why it would stumble slightly, it's driving me nuts.

If one cylinder isn't fully operating all the time due to lost spark or fuel or whatever the engine WON'T BREAK IN PROPERLY. If I can't ensure proper break-in I can't drive it. If just one cylinder fails to achieve proper seal, the whole thing is toast and needs to be torn down again, which I can't do.

How can I MAKE SURE I don't fuck this thing up?

-Chris Wood
 

·
Senior Member
Joined
·
1,568 Posts
Compression Check and Leak down are good place to start. Since Engine is new Leak Down will be a little high but should be consistant. Since you have a 91 you can get a pocketlogger to not only test the injectors and solenoids but also monitor fuel, knock, timing and etc.
 

·
vehicular thaumaturgist
Joined
·
8,289 Posts
Discussion Starter · #15 ·
Compression Check and Leak down are good place to start. Since Engine is new Leak Down will be a little high but should be consistant. Since you have a 91 you can get a pocketlogger to not only test the injectors and solenoids but also monitor fuel, knock, timing and etc.
Is pocketlogger the only datalogger that can do this? I hope I can figure this out w/o failing to break in the engine properly and without wasting time waiting to replace stuff that may or may not fix the problem.

One recent observation, the #3 plug (center front) is more oil-fouled than #1 or #5, AND when I pull the spark wire off the coil (while engine is running) it doesn't arc to itself or surrounding stuff nearly as much as the other coils do - I mean a noticable difference. The other plug driven off that coil, (the frontmost coil) arcs great (to the upper rad hose) when I take the plug wire off it. Is this a realistic symptom for a failed coil or am I seeing things? Could a coil arc well off one plug but not the other? Is there a good way to check with a multimeter or something?

-Chris Wood
 

·
Senior Member
Joined
·
1,568 Posts
The pocketlogger ( http://www.pocketlogger.com/ ) is not the only datalogger but I think its the best for the money and has a good support group. If you have Volume 2 of the Manual it provides 13 pages of troubleshooting steps for checking the ignition. For example the primary coil resistance should measure between 0.72-0.88 ohms and the secondary 10290-13920 ohms. The first thing you need to find is the oil leak. Plugs should not be oil fouled on new rebuilt engine. Good Luck.
 

·
vehicular thaumaturgist
Joined
·
8,289 Posts
Discussion Starter · #17 ·
For example the primary coil resistance should measure between 0.72-0.88 ohms and the secondary 10290-13920 ohms.
How can I test across each coil with a multimeter? I think I could figure it out, but I'd prefer to know the exact procedure.

The first thing you need to find is the oil leak. Plugs should not be oil fouled on new rebuilt engine. Good Luck.
Unless the heads were assembled improperly or something (I had them resurfaced and new valve seals installed), there is no way any oil could be leaking into the engine from anywhere out-of-the ordinary.

The plugs are NGK coppers that are one heat range colder than stock. I would think fouling would be "normal" on a new engine before it is broken-in and not being driven hard enough to heat up the colder plugs such that they self-clean.

I'm going to try replacing my PCV valve also - I want to buy a Krankvent at some point.

-Chris Wood
 

·
Registered
Joined
·
2,233 Posts
Multiades said:
One recent observation, the #3 plug (center front) is more oil-fouled than #1 or #5, AND when I pull the spark wire off the coil (while engine is running) it doesn't arc to itself or surrounding stuff nearly as much as the other coils do - I mean a noticable difference. The other plug driven off that coil, (the frontmost coil) arcs great (to the upper rad hose) when I take the plug wire off it. Is this a realistic symptom for a failed coil or am I seeing things? Could a coil arc well off one plug but not the other? Is there a good way to check with a multimeter or something?

-Chris Wood
I'd check the resistance of the spark plug cable, manual spec is less than 22K ohm. Easy part to check out.

Jeff
 

·
Senior Member
Joined
·
1,568 Posts
If the engine has been running for a period of time the extra oil as a result of the rebuild should be gone unless the plugs are not firing. Additional oil into cylinder can be coming fron valve stem seals, rings or intake if turbos are leaking. Hope the attached file will help with coil test.

 

·
vehicular thaumaturgist
Joined
·
8,289 Posts
Discussion Starter · #20 ·
If the engine has been running for a period of time the extra oil as a result of the rebuild should be gone unless the plugs are not firing. Additional oil into cylinder can be coming fron valve stem seals, rings or intake if turbos are leaking. Hope the attached file will help with coil test.
Helpful, I'll get right on it.

I am under the impression that an engine burns some oil before it is fully broken-in. Even if this amount is negligable, won't colder plugs foul automatically because they are not being cleaned by higher temperatures (assuming car is not being driven hard)?

Each front plug had a dark black ring around the base of the threaded part.

-Chris Wood
 
1 - 20 of 46 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top