Re: High Mileage PRV

[brobertson@xxxx]

Recently saw an '89 Volvo Bertone (B280) in jukyard with 180,000 miles
on odometer. If engine original to car, appears to have aged very
gracefully. No sign of fluids outside block. Only wanted $150 for
everything forward of transmission. Had mileage been lower might have
considered buying. Seriously covet that 10.5:1 compression.

Bill Robertson
#5939

>--- In dmcnews@xxxxxxxxxxxxxxx, abbotts@xxxx wrote:
> The PRV's poor reputation is only partially deserved IMHO. My feeling 
> is that the early versions had some design and manufacturing flaws 
> which can be overcome with a bit (a lot?) of work. One of the worst 
> flaws is the engine's propensity to leak coolant into the oil when 
> the cylinder sleeve seals fail. I have a strong suspicion that the 
> sleeves did not have enough protrusion above the block when these 
> engines were first assembled at the factory. This could contribute to 
> blown head gaskets also. The fix requires a full rebuild. Check the 
> sleeve protrusion. I bet its nowhere near enough even with the 
> thickest available seal fitted to the base of the sleeves. Cure? 
> Simple (relatively!). Have the block decks machined to achieve 9 
> thou protrusion with the thickest seal (yellow one) fitted. Only 
> needs about 3 thou or so taken off on average, so doesn't measurably 
> affect cam chain tension. So long as the protrusion is the same for 
> all 3 sleeves on each bank and they are square with the block and 
> each other, that *should* hopefully take care of any future concerns. 
> The other problem I have suspicions about is low oil pressure due to 
> faulty oil pump relief valve springs. My engine showed precious 
> little oil pressure on a gauge, but the idiot light on the dash 
> rarely came on. Geez, what are those switches set at, about half a 
> psi? When I disassembled the oil pump the spring was in 8 bits. 
> That's not a one-off failure, that's a badly made spring. Early V6's 
> were known for hacking up valve train components due to a lack of 
> lubrication. Haven't got proof, but my gut feeling is that the cause 
> could be primarily due to bad oil pump springs leading to oil supply 
> limitations to the top end of the engine. Don't know for sure, just a 
> hunch. How many folks would bother to routinely pull the oil pump 
> (not an easy job) just to check it out?
> Otherwise (French design quirks excepted) its a nice little engine. 
> The later B280 version fixed the odd firing sequence by offset 
> grinding of the crank throws to even things up. Heads were modified 
> and given oil 'wells' for the cam lobes to dip into each revolution. 
> Cams were re-designed to give a bit more grunt and a little better 
> fuel consumption, the silly distributor position of the early 
> versions was altered. My B28 had covered over 200,000 km when I 
> pulled it apart due to the busted oil pump spring. The bottom end, 
> including the bores, showed virtually no wear at all. A quick 'glaze 
> break' and a set of new rings and bearings just to be on the safe 
> side and it should be good for another several hundred thousand km. 
> Hopefully :)
> Our local machine shops and Volvo dealerships have never yet had a 
> B280 apart. Some of them must have accumulated pretty high mileage by 
> now. Must say something for the longevity of those engines I guess. 
> And for a V6 they are remarkably smooth. Considering the modest power 
> output, it'd be nice if the fuel consumption was a bit better though.
> 
> Cheers
> Steve Abbott
> 
> --- In dmcnews@xxxxxxxxxxxxxxx, brobertson@xxxx wrote:
> > Factory was in France, but Swedes have their fingerprints on design 
> too.
> > 
> > To be honest, Volvo's final rework of original design (B280) is very
> > nice engine, EFI not withstanding.
> > 
> > I was very leery about PRV before actually getting my hands on one
> > (original posts to DML regarded Vortec conversion). Now, am rather
> > fond of the little powerplant. Has its weaknesses: "Internal" water
> > distribution pipe is assinine. Ignition distributor would have been
> > better relocated by cylinder #3 (as it is on B280). Clearance is 
> tight
> > among injectors and spark plugs. But in all PRV is surprisingly 
> smooth
> > running (given odd fire sequence) with good bottom end torque and
> > projected long life span -- Bertone I saw in Hagarstown junkyard had
> > 180,000 miles on odometer.
> > 
> > JZD could have chosen worse.
> > 
> > Bill Robertson
> > #5939