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Discussion Starter #1
Just received a barn find GTV with a CF2 3.0 motor and 130k on the clock.

Before trying to start it, I removed the cam covers on both banks to inspect the cams, add some oil, and run a compression test... which revealed no compression at all on cylinders 1 and 6, with normal pressure on the rest.

The engine fired reluctantly and ran very roughly... albeit without any knocking or other concerning noises.

I didn’t leave it to run for too long but the coolant is filthy and bubbles were starting to appear in the header tank after a few minutes.

There are no errors on the engine ECU when read via MES.

I’m assuming this means both head gaskets have failed; but would this lead to the rough running - as though the motor was only running on four cylinders?

And is this a typical failure pattern on these engines - ie, cylinders 1 and 6?

I’m happy to put the work in to replace the head gaskets, but want to rule out other causes of the misfire first...

Thanks in advance!
 

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There are plenty of other things to look at before you do the head gaskets. Do you know why it was stored in the first place? Was it running Ok when they stopped using it. HGs don't generally fail in storage! Could be a couple of slightly sticking valves, rings gummed in there grooves on the pistons. Bubbles in the coolant could be just air in the system being driven out. Replace the coolant and oil run it up and see if she settles down. A bit of heat through a motor that's been stored can free of a lot of things. Put a drop of oil in the low compression bores, do another compression test and see if it comes up a bit on compression. A blown head gasket generally would not leave you with zero compression when cranking on the starter anyway....you need a broken piston or a partially open valve for that. Good luck with it!
 

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There are plenty of other things to look at before you do the head gaskets. Do you know why it was stored in the first place? Was it running Ok when they stopped using it. HGs don't generally fail in storage! Could be a couple of slightly sticking valves, rings gummed in there grooves on the pistons. Bubbles in the coolant could be just air in the system being driven out. Replace the coolant and oil run it up and see if she settles down. A bit of heat through a motor that's been stored can free of a lot of things. Put a drop of oil in the low compression bores, do another compression test and see if it comes up a bit on compression. A blown head gasket generally would not leave you with zero compression when cranking on the starter anyway....you need a broken piston or a partially open valve for that. Good luck with it!
I agree 100% with the above.
 

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Discussion Starter #5
Thanks for the advice - and you’re right, no compression at all is far more likely to be caused by valves sticking open than by a HG failure.

To answer some of your questions... I don’t know why the car was mothballed; and I don’t have the kit to run a cylinder leak test. But I do like the idea of running the engine fully up to temperature on some fresh coolant - not least to check that the cooling fans work.

However - now the darn thing won’t start at all!

So I’m going back to basics:

- checking there’s a spark on each cylinder (yes on the front bank, will check the rear bank tomorrow)
- checking there’s fuel at each cylinder (tomorrow)
- checking the engine-to-earth connection is good (despite a fresh battery, the crank speed seems slow compared with the Busso in my 166...)
- check the throttle valve is responding
- MES is still showing no errors apart from a lambda sensor gone open circuit

So... anything else I should be checking?

Would the lambda error stop the car from starting?

I’m really hoping the starter motor is not crocked as that does not sound like an easy job to replace...
 

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There are plenty of other things to look at before you do the head gaskets. Do you know why it was stored in the first place? Was it running Ok when they stopped using it. HGs don't generally fail in storage! Could be a couple of slightly sticking valves, rings gummed in there grooves on the pistons. Bubbles in the coolant could be just air in the system being driven out. Replace the coolant and oil run it up and see if she settles down. A bit of heat through a motor that's been stored can free of a lot of things. Put a drop of oil in the low compression bores, do another compression test and see if it comes up a bit on compression. A blown head gasket generally would not leave you with zero compression when cranking on the starter anyway....you need a broken piston or a partially open valve for that. Good luck with it!
Totally 100% agree, and you definitely don't want to try running it before you've given it a full checkover, including checking the bores for corrosion - you might find horrors like this when you drop the heads off :yuck:





See my thread about the two Bussos I've recently pulled apart - both were in fine condition when laid up, but definitely weren't a few years later...

https://www.alfaowner.com/Forum/alfa-75-rz-sz/1178525-busso-12v-engine-rebuild-help-opinions-needed.html

I'm assuming yours is a 916 gtv as opposed to a 116 gtv with a 3.0 conversion so with a bit of luck it might not have been standing around for years, but at the very least turn the engine over by hand to see if you can feel any points where it binds, which might suggest rust in the bores. And maybe, if you're nimble enough or have an endoscope, drop out all the plugs and check out the condition of what you can see of the pistons / bores.

BTW your non-starting issue might be immo related if it's a 916 gtv - immobilizer problems used to be very common and resulted in many 3.0 v6s ending up off the road before anyone knew how to fix it, or even just a +12v or ground issue - those battery cables have an awfully long way to run from the boot to the starter.

Edit2: I hope you checked the condition of the cambelt before trying to run it btw, otherwise you might have given yourself a few more issues than you started with!
 

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Discussion Starter #8
Can you hear the fuel pump prime up with ignition on? it is behind the rear seat
Yes - the pump is working and fuel is definitely getting as far as the union with the fuel rail...
 

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Discussion Starter #9
I'm assuming yours is a 916 gtv as opposed to a 116 gtv with a 3.0 conversion so with a bit of luck it might not have been standing around for years, but at the very least turn the engine over by hand to see if you can feel any points where it binds, which might suggest rust in the bores. And maybe, if you're nimble enough or have an endoscope, drop out all the plugs and check out the condition of what you can see of the pistons / bores.

BTW your non-starting issue might be immo related if it's a 916 gtv - immobilizer problems used to be very common and resulted in many 3.0 v6s ending up off the road before anyone knew how to fix it, or even just a +12v or ground issue - those battery cables have an awfully long way to run from the boot to the starter.

Edit2: I hope you checked the condition of the cambelt before trying to run it btw, otherwise you might have given yourself a few more issues than you started with!
Yes, it’s a 916 GTV... cambelt is intact (although it and its rusty idlers should be replaced). Immobilizer seems to be OK - CODE light switches on then off when the ignition is switched on (as do ABS and airbag warning lights...). Assuming the injectors aren’t blocked I’m currently thinking either the starter motor is not earthing correctly - or it’s knackered...

I’ll do more digging tomorrow!
 

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So the starter motor doesnt turn at all?

If so, stick it in gear and push the car, most of the time it's just not engaging right and the push fixes it.
Especially likely if the car's been standing for some time - the grease tends to congeal after an extended layup.

Any idea how long the car was off the road for, @JeremyG ? MOTinfo might give a useful clue if the seller didn't tell you.
 

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Discussion Starter #12 (Edited)
Yes, last MoT expired just over 5 years ago...!

The starter motor is working, it just isn't turning the engine over very fast - despite using a new Bosch battery (which I'm keeping charged up between fruitless bouts of engine turnover... ;-)

I have spark and fuel on every cylinder. I've fitted new spark plugs.

The throttle body is not in a good state - it whirrs constantly when the ignition is on, and only opens a little on full throttle - see pic below. That obviously needs fixing, but I'd still expect the engine to start. And it still wouldn't start with the throttle body removed from the plenum - effectively on max throttle! I think my 166 has the same TB so I can try a switch over the weekend.

If I do decide to pull the starter motor, I gather it will come out from above - although it is the item circled below - hidden under the exhaust manifold and a heat shield at the back of the engine? Lovely... I might start a separate thread to ask about that one...

EDIT: turns out the (identical) throttle body in my 166 behaves the same... it makes a (quieter) whine, and will only open a few degrees with the throttle pedal on the floor but the engine not running...
 

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Yes, last MoT expired just over 5 years ago...!

The starter motor is working, it just isn't turning the engine over very fast - despite using a new Bosch battery (which I'm keeping charged up between fruitless bouts of engine turnover... ;-)

I have spark and fuel on every cylinder. I've fitted new spark plugs.

The throttle body is not in a good state - it whirrs constantly when the ignition is on, and only opens a little on full throttle - see pic below. That obviously needs fixing, but I'd still expect the engine to start. And it still wouldn't start with the throttle body removed from the plenum - effectively on max throttle! I think my 166 has the same TB so I can try a switch over the weekend.

If I do decide to pull the starter motor, I gather it will come out from above - although it is the item circled below - hidden under the exhaust manifold and a heat shield at the back of the engine? Lovely... I might start a separate thread to ask about that one...

EDIT: turns out the (identical) throttle body in my 166 behaves the same... it makes a (quieter) whine, and will only open a few degrees with the throttle pedal on the floor but the engine not running...
Yes, it is an electronic TB and whirls when ignition and and on full throttle it opens only partly. I have seen your other post regarding the timing on the engine and it probably does not run bacuse timing is way off. Just hope that valves are not bent since you have no compression. Try hooking compress air to the cyllinder and listen where the air comes out (leakdown test). You can also try smoking the cyllinder and checking where is the smoke leaking. These engines are extremely sensitive on timing. IMHO you should not have even rotated the engine before changing the cambelt and verifying timing. Good luck!
 
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