Engine diagnosis help

JimD

Waiting for Godot...
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I got a call for help from a new Fiat acquaintance here in STL. He has an 86x that was running a couple years ago, then had an over heating issue. The shop he took it to said they thought it was the head gasket, supposedly worked on the engine, but did not fix the car properly. He has been trying to figure it out off and on ever since. I do not know any other history of this engine.

Right now, the engine rotates slower than I think it should. Battery had 12.5v. I told him we will probably have to start taking engine parts off and looking for trouble. I drove my 86X over today and we did some "stare and compare" and found a couple wires and vacuum lines that were disconnected or not connected properly. We set the plug order to be the same as my X. Here is what it sounds like when cranking. It sure doesn't sound right.


There is lots of gas in the oil from all the cranking without a start up, so that will need to be changed. I told him to check the timing first, then we will look at checking the valve adjustment. We did get a couple muffled pops, but compression is another thing we need to test.
 
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It definitely doesn’t sound the way I would expect and is way slower than it should be.

Battery could use a charge.

Check the engines mechanical timing set up, I would suspect there is something not right there.

It doesn’t sound like there is any spark, did you happen to have a timing light on it to see if there is any?

I would do a compression test to see if they even got the engine back together properly.
 
I have been thinking on this some more. The oil we saw in the cam box when looking thru the oil cap opening looked milky? That is the sign of a head gasket failure with the mixing of oil and coolant. We also pulled the dipstick and commented on the gas content, but also that the oil looked like oil and felt like oil.

So a non-Fiat experienced shop pulled the head and "fixed" the engine. I wonder if they put the new gasket in upside down. I believe that blocks off the oil supply for the cam box. Right? At least, I can't think of another explanation for why the oil looks so different in these two normally connected engine areas. There wasn't a lot of oil in the cam box either, it was more like a puddle in the corner where we could see. I could clearly see the closest sims were not in an oil bath. I think they are usually covered in a pool of oil.

The lack of lube up there might explain the slower rotating sound when trying to start it.
 
I'd start with the basics. Do you have fuel, spark, compression and timing? All easy to check and at least one of them is missing. Not uncommon to have some water in the oil by the areas that get exposed to the atmosphere like a poorly sealed dipstick, breathers, oil caps, etc due to condensation. It sounds like there isn't spark from the video.
 
I'd start with the basics. Do you have fuel, spark, compression and timing? All easy to check and at least one of them is missing. Not uncommon to have some water in the oil by the areas that get exposed to the atmosphere like a poorly sealed dipstick, breathers, oil caps, etc due to condensation. It sounds like there isn't spark from the video.
Thanks Paul, we will be digging in more as time allows. We got a couple little pops, but we will do all the checks. I should have taken a picture of the oil I could see. I will get more pictures as we get into the process of diagnosing. The car is across town from me, so I don't have ready access to it, nor the time to dedicate to a thorough investigation right now. Real life issues are always interfering with the Fiat life. :(
 
The owner pulled the valve cover this morning and sent these pictures. That looks pretty dry.
IMG_20210503_110843.jpgIMG_20210503_110852.jpg
 
Yeah, that's very dry; I wouldn't turn it over any more without at least pouring a bit of oil on the cam.

If I were in your socks, I think I'd want to spin the oil pump (using a tool on a drill motor) to check for oil pressure before doing much else.
  1. If the pressure comes up and oil appears around the cam, I'm happy and I can go on to testing compression and whatnot.
  2. If the pressure comes up and oil doesn't pump up to the top end, I'd think I need to disassemble from the top down until I find the cause.
  3. If the pressure doesn't come up, I believe I'd drop the motor.
 
Sounds about right Dale. After seeing the pics, I advised the owner to pour oil up there then turn the engine by hand. Patience will be required, there probably is no quick fix here.
 
When you say "pops", the first thing that comes to mind is dist cap is 180* off.
I think we will just start from square one on this engine. Then test and test until we finally give in and tear the engine down. I have a spare 1500 that came with my raceX, perhaps it is a better candidate for a rebuild at this point. I will check that engine out as well.
 
The cam still looks ok, just not as much oil as I would expect to see.

Putting some oil on the cam lobes would ease that and then turn it over to see if it is actually pumping up to the top would be worthwhile as a check for oil pressure. If no pressure I would bet it is the head gasket being flipped. The alternative is to remove the dist, the timing belt and spin the pump up that way to see if its a failed gear or possibly a failed pump (unlikely on both counts as they aren’t the delicate part of these engines).

With the cap off and the timing marks lined up for number four, where is the rotor pointing? In the original video it was giving no indication of any spark. The #4 post of the factory type cap is directly above the vac advance attachment screw.
 
The cam still looks ok, just not as much oil as I would expect to see.

Putting some oil on the cam lobes would ease that and then turn it over to see if it is actually pumping up to the top would be worthwhile as a check for oil pressure. If no pressure I would bet it is the head gasket being flipped. The alternative is to remove the dist, the timing belt and spin the pump up that way to see if its a failed gear or possibly a failed pump (unlikely on both counts as they aren’t the delicate part of these engines).

With the cap off and the timing marks lined up for number four, where is the rotor pointing? In the original video it was giving no indication of any spark. The #4 post of the factory type cap is directly above the vac advance attachment screw.
Thanks Karl,

I haven't had a chance to get back over to the engine. We will check it all out once I have time to get back to it.
 
We were playing with it again this morning: we set the static timing at 10 degrees BTDC, then checked that the rotor was pointing at #4. Sprayed some starting fluid in the intake just for fun, but it still won't start. It cranks, all the wires seem to be hooked up, battery charged, we get spark if we put a plug up to the block, but noy joy. The rotation of the engine seems sluggish when cranking. It just doesn't sound "free" if you know what I mean. We can rotate it fairly easy with a socket on the crank nut. It isn't buttery smooth, but its not a wrestling match either.

One thing I learned today is that the car has never run since the shop supposedly replaced the head gasket. The shop couldn't make it run either apparently. This engine may just be toast, but what do I know.

I noticed that the fuel pump wasn't activating with the key, so I swapped in a new multi-relay on a whim. Nothing changed. So I unplugged the new relay and plugged the old relay back in and the fuel pump came to life... without the key in start or on position. Even taking the key out didnt phase this pump. That is probably not good. I put the new relay back in and the pump still runs non-stop.

I think we need a real mechanic or perhaps a exorcism. :(
 
Sounds like an electrical issue. That takes time to trace and test all of the involved circuits. Perhaps the shop reconnecting the wiring wrong when they did the head gasket.
 
When the shop pulled the head the timing belt was removed, did anyone doublecheck that the reinstall was done correctly?
 
They clearly put it together wrong, I am with JimmyX on this. The electrics are clearly eff'd as well though the flap in the AFM could be stuck open.
 
They clearly put it together wrong, I am with JimmyX on this. The electrics are clearly eff'd as well though the flap in the AFM could be stuck open.
Thanks guys, the actual history of this repair is a mystery. I will check the AFM flap next time I get over there. I will also look into cyl 1 and see if the piston looks to be at or near TDC when the marks are lined up. The cam and crank marks never align perfectly, they are like a half tooth out. That seemed close enough to expect it to fire or at least get some trying to fire action.

The owner has been trying various ideas when I am not available and I am pretty much in over my head at this point.
 
Sounds to me like the motor is way out of time. Maybe they didn't get the timing belt back on correctly? I had my belt changed may years ag by a "foreign car specialist". When I picked it up, it ran, but had no power. He fixed it, but never admitted the belt was off a tooth or so. He just said it needed an "adjustment. Needless to say I never went back.
 
Sounds to me like the motor is way out of time. Maybe they didn't get the timing belt back on correctly? I had my belt changed may years ag by a "foreign car specialist". When I picked it up, it ran, but had no power. He fixed it, but never admitted the belt was off a tooth or so. He just said it needed an "adjustment. Needless to say I never went back.
I will have check it before we give up. I haven't removed the belt and reinstalled it, so it is set up however the shop installed it. The marks do line up pretty close, but it is possible the crank is 180 out.
 
The cam and crank marks never align perfectly, they are like a half tooth out.
Most of mine are that way, even when the cam timing is perfect. I've checked the position of each timing marker, verified TDC, verified the cam position, etc, etc, and it still looks about a half tooth off. I just mark it up to being a Fiat.

but it is possible the crank is 180 out
That's possible. Especially if the flywheel was already 180 out but the prior owner compensated for it with the belt setup, however the shop wasn't aware of that and set it up according to the flywheel. Really a shame Fiat did not add a dowel or make the flywheel mounting bolt pattern asymmetrical so it could not happen.

Although I've seen these engines still start and run(ish) with the cam belt way off. I even had one that was 180 out and you could still drive it - sort of. So I agree with you that it should at least want to start. This whole thing is sounding more like a electrical issue to me, perhaps with the FI system. That weird thing with the dual relay was a big clue to me.
 
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