Volvo 850 10v to 20v Conversion.

[scot850]

The 10V engine is a sweet engine if not powerful. I had a 20V in an 850 and it was reasonably peppy but had less low down torque which meant with an automatic trans you had to keep the revs up to get any zip out of it. Same with the LPT and HPT engines. The smaller turbos give more low down torque which for windy roads is better in my opinion.

Each to their own. Lot of oil blow by could also be a PCV clean out needed. At 230,000km the car is barely run in!

I would suggest having your Dad help check the existing motor over carefully, doing a compression test on it and check the PCV system (glove on the oil filler cap hole with cap removed) to see where you are. If the PCV needs done, then as you have to take the inlet manifold off for that, not too much more to pull the head and service it.

Good luck which ever way you go!

Neil.

[misha]

Ok.
Does it blow the blue smoke all the time,after idling a bit and when you take off after that?
Does it clear off after acceleration?
Could be clogged PCV or thin oil in the engine.

Do you have positive crankcase pressure from oil dipstick and from oil cap?

[2ndGenVolvos]

At 280K ...valve stem seals could also be a problem at that 20v engine.
Weak point on these cars.

You don't check ecu for a mileage...you check instrument cluster...since the mileage is stored in the cluster module.

ECU actually does track mileage. You need the volvo scan tool to access the information though. I have one from when my dad used to work at Volvo Canada. My Odo reads 223,000 but the actual mileage is around 230,000. The gear broke but was changed fairly quickly given that they often go unchanged on these cars.

[2ndGenVolvos]

Ok.
Does it blow the blue smoke all the time,after idling a bit and when you take off after that?
Does it clear off after acceleration?
Could be clogged PCV or thin oil in the engine.

Do you have positive crankcase pressure from oil dipstick and from oil cap?

When I test drove the car it didn't blow blue smoke. I drove behind it the whole way home (about a half-hour drive). And it didn't have any blue smoke until we pulled onto my street. Since then, it billows the more I put my foot into the gas. Oil levels are good, might have old oil though.
I have yet to do any tests for crankcase pressure.

[2ndGenVolvos]

The 10V engine is a sweet engine if not powerful. I had a 20V in an 850 and it was reasonably peppy but had less low down torque which meant with an automatic trans you had to keep the revs up to get any zip out of it. Same with the LPT and HPT engines. The smaller turbos give more low down torque which for windy roads is better in my opinion.

Each to their own. Lot of oil blow by could also be a PCV clean out needed. At 230,000km the car is barely run in!

I would suggest having your Dad help check the existing motor over carefully, doing a compression test on it and check the PCV system (glove on the oil filler cap hole with cap removed) to see where you are. If the PCV needs done, then as you have to take the inlet manifold off for that, not too much more to pull the head and service it.

Good luck which ever way you go!

Neil.

Thanks, Neil, I appreciate the insight. I'll run a PCV test in the next few days to figure out if it needs to be done.

[xanthefin]

You maybe want check if 20V pistons has some extra cuts for 4 valves to prevent them hitting them but i can be wrong on this.

Well I'd assume I'd need to replace the pistons anyway if they're bad enough from the oil burning. Who knows whats actually going on inside the engine. It might just be more sensible to swap out the motor.

No need pistons if not replace with 4 valve head..

Case of point is here as pistons are on purpose different on 20V head vs 10V
https://www.matthewsvolvosite.com/forum ... 24#p391324


For to do maintanence for 10V.. piston rings are good call to do if you go so deep anyway. They usually can be stuck and dirty after decades but to make blue smoke i don't believe is cause.

Valve seals are common let oil through as they getting old and brittle specially for me in summer i can get on hot days blue smoke start ups easily. Did to my previous car replace them.. but did pistons too that time as i opened more.

PVC is one headache on these in my opinion.

[misha]

...ECU actually does track mileage. You need the volvo scan tool to access the information though. I have one from when my dad used to work at Volvo Canada. My Odo reads 223,000 but the actual mileage is around 230,000. The gear broke but was changed fairly quickly given that they often go unchanged on these cars.

Yes...you need volvo scan tool,but the mileage readout is from the cluster itself because it is stored there.
Even if gears are broken and odometer stopped at some mileage....the cluster microprocessor is still working and it keeps tracking the mileage after odometer gears are broken.
Big number of dealerships worldwide doesn't even know how to read actual mileage.

Been there....done that in "stealership".

[2ndGenVolvos]

You maybe want check if 20V pistons has some extra cuts for 4 valves to prevent them hitting them but i can be wrong on this.

Well I'd assume I'd need to replace the pistons anyway if they're bad enough from the oil burning. Who knows whats actually going on inside the engine. It might just be more sensible to swap out the motor.

No need pistons if not replace with 4 valve head..

Case of point is here as pistons are on purpose different on 20V head vs 10V
https://www.matthewsvolvosite.com/forum ... 24#p391324


For to do maintanence for 10V.. piston rings are good call to do if you go so deep anyway. They usually can be stuck and dirty after decades but to make blue smoke i don't believe is cause.

Valve seals are common let oil through as they getting old and brittle specially for me in summer i can get on hot days blue smoke start ups easily. Did to my previous car replace them.. but did pistons too that time as i opened more.

PVC is one headache on these in my opinion.

I need to do more research on the wiring similarities between the 10v engines and the 20v. Ideally, I'll find a way to run the 10v without changing the ECU from Fenix 5.2 to the correct one for the 20v.

I get a discount on parts from the dealership since my dad works there so it will be a little less expensive for me to do this conversion but from what I understand I'll need, at the very least, the 20v head, 20v intake manifold, 20v exhaust manifold, and the 20v pistons for the correct release for the 20v head.

I'm going to check my PCV with the glove test tomorrow or friday and see what is going on with that. I wouldn't be suprised if that needs to be done too.

[2ndGenVolvos]

...ECU actually does track mileage. You need the volvo scan tool to access the information though. I have one from when my dad used to work at Volvo Canada. My Odo reads 223,000 but the actual mileage is around 230,000. The gear broke but was changed fairly quickly given that they often go unchanged on these cars.

Yes...you need volvo scan tool,but the mileage readout is from the cluster itself because it is stored there.
Even if gears are broken and odometer stopped at some mileage....the cluster microprocessor is still working and it keeps tracking the mileage after odometer gears are broken.
Big number of dealerships worldwide doesn't even know how to read actual mileage.

Been there....done that in "stealership".

Hmm that's very interesting. Whether my scan tool read it from there or the ecu doesn't really matter though I still know I've got about a 9 thousand km difference between the two, which is not that bad.
My s40 T5 AWD had an engine swap and the engine has 190k and the body has got 252k. Much bigger difference.

[scot850]

I would also remove the spark plugs and have a look at the plugs for condition. They may give an indication on what is happening in the cylinders. Then do a compression test.

Are you sure the smoke is oil and not fuel? Does the temperature gauge read correctly?

Try changing the oil. If someone used too thin an oil, then it will blow by the pistons into the combustion chambers. Put a fresh oil filter in and try filling with 10W-30 high mileage oil and see if there is a difference.

Neil.