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'01 ph2 916 Spider 2.0ts Zoe Yellow
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Discussion Starter #1
Hello! I'm new here - owned a couple of Alfas but never posted on here before!

Seeking advice..

Picked up a 2001 ph2 spider TS that had been sat in a garage for years. Changed all the fluids, got her running, but she started to knock... I suspected big end bearings...

I'd assumed that the cheapest/best way to sort this out would be to stick a used engine in, which I managed to source.

Old engine is out of the car, and I've managed to have a closer inspection of the bottom end - looks like big end bearing number 4 has spun - it was not seated properly in the end cap, and has marks on it. (see picture 1).

From what I can see, the Crank is not marked.. (see picture 2) so I'm wondering whether to just do the shells and stick the car's original engine back in, or put the new (used) engine in just in case..

If going with the new engine I'd do the shells anyway since they're cheap, and replace all the other bits (belts, water pump, variator, clutch)

The old engine is CF3 has 58,000 miles
The new (used) engine is CF2 has 100,000 miles and I don't know the history other than that it's had a recent headgasket.

So something tells me I'd rather keep the original engine with the car if at all possible..

1) Thoughts on a plan of action?!

2) I've heard before that big end bearing failure can cause top end damage - surely the movement in this case wouldn't be enough for the piston to have an altercation with the valves?


IMG_20200719_170549.jpg
IMG_20200719_170553.jpg
 

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If it were me I'd go with the original engine. It's known to you and with a good inspection and flush of old oil should go on for a good while. The unknown engine could have other issues you might not know about until you've done all that work and start it up!
I bought a replacement motor once for my 33. Was told it was a good runner but ended up taking the damn thing out again as one of the valves had part of it missing.....
 

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I'm with Harvo on this one. Better to have the original engine in the car especially as it has done a lower mileage overall. You or someone else in the future might thank you when they are really valuable (you never know they might be one day!) and someone checks and finds it is not the original engine and the value drops by 20%. Probably not in my lifetime but we can always hope!

I replaced the shells for the big end and main bearings on my V6 as I didn't like the looks of the wear on the rear main bearing cap which I removed to fit a new oil seal (see here). The actual crank journal looks good by eye but it is worth getting it checked and the journals polished at a good engineering shop if you are going to the trouble. And use an assembly lubricant when you put it back together to protect the shells before the oil pressure comes back up and the oil ways fill. Are you sure the bearing was spinning? It must take a hell of a lot to flatten the recess. Are they standard size or has the crank been re-ground previously and oversize bearings fitted? I might be more wary if it has been done before and failed again.
 

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This might help you with the diagnosis. It looks like the link in my thread has gone. Link. Oh and btw I don't think you will have top end damage because of this as long as there isn't something wrong at the top end that has caused this problem at the bottom.
 

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'01 ph2 916 Spider 2.0ts Zoe Yellow
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Discussion Starter #5
This might help you with the diagnosis. It looks like the link in my thread has gone. Link. Oh and btw I don't think you will have top end damage because of this as long as there isn't something wrong at the top end that has caused this problem at the bottom.

That's great. Really helpful.

Agreed that keeping the original engine with the car would be preferable.

The wear on the bearings look like oil starvation... Which makes sense A) because the guy who had it before said he just started it a couple of times after long periods of being sat.. And B) because the only sign of excessive wear is on the bearing furthest from the oil pump.

The part number on the bearings is 46738845 which is listed as
FIATHALF BEARING -0.254
I imagine these are standard being Fiat Branded, but am not entirely sure... I don't have a micrometer to measure the Crank, but as you say. It is probably worth me taking it out and sending it to a machine shop anyway.

That way the mains can be checked as well. Getting to my limit of mechanical knowledge but I'm learning a great deal!

Should I be worried about the apparent marking on the end caps & con rods? (pictured)

IMG_20200720_163734.jpg
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I could be wrong but I believe that the CF2 and CF3 Twinnie engines are subtly different. I think they have different compression ratios so running a CF2 engine with a CF3 ECU may cause issues.
 

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I wouldn't be concerned about the marks on the con rods or caps that seems pretty normal, as long as they feel smooth and no obvious imperfections in the surface? Any raised spots will apply pressure to the bearings and cause premature wear on the bearing face when tightened up. I need to check but it wouldn't surprise me if the -0.254 might mean that they are over sized (-.254 mm). I might be wrong as I seem to recall that they measured each crank and then fitted slightly different bearings but I thought they were colour coded in some way to differentiate not stamped. I don't recall anything but the part number on mine. I might be concerned if that is the only one to show wear that there could be flow restriction in the oil way (blockage) to that journal or perhaps that the oil pump is not generating enough pressure as you mention it is the furthest bearing from the pump.
 

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Well I am confused now. If you put that part number into EPER it does indeed come out for a big end bearing shell but the models to which they are fitted are the Fiat Bravo Brava and Marea no mention of the GTV. They do also seem to be replacements for a reground (undersize) crankshaft journals. Have you tried typing your VIN into EPER and seeing what the engine number was as it came out of the factory? You could then check against this engine number. I don't know much about twinnies but could this already be a replacement engine but from a Fiat? Is it more or less the same engine?
 

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'01 ph2 916 Spider 2.0ts Zoe Yellow
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Discussion Starter #9
Well I am confused now. If you put that part number into EPER it does indeed come out for a big end bearing shell but the models to which they are fitted are the Fiat Bravo Brava and Marea no mention of the GTV. They do also seem to be replacements for a reground (undersize) crankshaft journals. Have you tried typing your VIN into EPER and seeing what the engine number was as it came out of the factory? You could then check against this engine number. I don't know much about twinnies but could this already be a replacement engine but from a Fiat? Is it more or less the same engine?
Yes, the Fiat listed bearings is curious. But it wouldn't surprise me if Alfa weren't consistent with this in the factory!

The engine code on the block is AR32310 - so Alfa rather than Fiat because I believe fiat use a different numbering system, but the number below that (2105060174) I do not recognise. Seems to be too many digits to be an engine number, but could be wrong...

The bearings are colour coded from new but the colours soon wear off so as I understand you can rarely identify them by colour once they've been used.

I'll get the Crank measured and go from there.

I do always have the Crank from the spare engine - if that one hasn't been reground it might be preferable to use that Crank.

Thanks again for your responses!
 

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It would be good to know how it works out so please come back and let us know. As I mentioned if you go the the FIAT forum website they have a copy of EPER running on their website here. It is a bit flakey as to whether it works or is running slowly but you can usually navigate through to the Alfa spare parts catalogue. At the bottom of the page you can enter your VIN and this version will tell you all the details about the car when it left the factory including engine number (at least it does for mine). At least you will know what number you are looking for and if it is the original engine. Good luck!
 

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I have done a bit more homework and they are undersize bearings so it has been reground before. For some reason there are no undersize bearings listed for the AR engines but if you use the part number for the standard sized bearings on the same FIAT engine as I mentioned above then those are fitted to a whole range of FIAT/Alfa engines including the AR32310. Not surprising as the block in various sizes is common to a number of different FIAT/Alfa/Lancia engines but the heads vary hence the TS version on the GTVs. If the crank and journals are OK then perhaps just polish and fit undersized again but if the other big end and the main bearings look OK you have to ask why that one has been so badly affected. If they are all as bad then oil starvation may be the cause but due to what?
 
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