1995 into 1999 engine swap thread , Mike 2012

[precopster]

Well I brought the head to the local machining guy, Graham, who has been very helpful and patient in explaining the whole process to me.

It is warped at around 15thou across the combustion face and around 10thou across the cam journals, so this explains the lack of compression; all gases were escaping past the head gasket.

Graham is a very capable head specialist and he says he can straighten it with some pressure in the centre and a good machining, though he recommends changing the guides and stems during the process. Around $700 all up. I almost fell over because I still don't know if my spare 10 valve block will become a 20 valve block by simply swapping the pistons from a dismantling yard.

Apparently the oil pressure thread and sump is totally different on the '99 model block but I need to see this for myself.

An entire low mileage engine from a '99 model will set me back around $1,300 so this may be the way to go.

Am going to have another look at the block this weekend and see if the rust can be sanded from the bores.

[SimLyons]

You say early on that the sump was really dry when you pulled the drain plug. Did the previous owner remove the oil or ...???

If the engine was run any length of time with no oil that would account for some nasty damages to all areas/parts dependent on lube oil for cooling as well as lubrication. It could have led to overheating and coolant loss, head warpage, blown gaskets, seizure, etc.

Also,that chunk of aluminum must have gone somewhere...out the exhaust via the turbo? Or past the eings (in fragmants)and into the oil pan, or both?

Personally, I would replace the engine as your latest comment suggests.

I think you have a nice boat anchor there.

[precopster]

Drain plug wasn't pulled, that is yet to happen, the oil didn't show on the dipstick until I had poured at least two litres of oil in. Engine turns over very easily suggesting no bearing failure, but this is not definitive.

It's an NA so no turbo damage, that chunk is probably in the catalytic converter now!! Don't know how it got past the valves without damaging them.

[precopster]

So I'm almost ready to pull the engine. I've had a B5252S (2435cc) 10 valve block fully stripped on the workshop bench for a couple of months (waiting for warmer weather) and from the measurements I've taken all important dimensions are identical to the '99+ blocks except for a bolt hole for a 10mm bolt to help support the fuel line and an extra accessory bracket bolt hole as pictured. The sumps are different but I'm almost certain that I can bolt the '99 sump to the early '95 block.

Also the location of one of the knock sensors is different but the PCV locating holes are identical.

Also from photos and measurements I've taken the pistons from '95 model 20 valve NA 850 should be the same a the '99 model 20 valve NA pistons but as I haven't removed the pistons from '99 block yet the verdict is out on this.

If all goes well I may be the first guy to have a 20 valve '99 model V70 with a block stamped B5252S !!

[precopster]

Ok so I decided it would be best to source another engine from a pick and pull. I found a near new 20 valve engine with 195-205 psi on all cylinders.

It was fitted to a '95 850 GLT (NA) with around 76K miles that had been made it to the graveyard. Honestly the only thing I could say that was a annoying fault on this car was that the door stay bracket on the frame had ripped away and was making the trademark clicking noise (a problem I repaired on my 850 wagon by removing the door and tapping in some bolts where the factory welds had snapped)

Oh and it had a small scrape on the boot and a broken tailight. Two day's work for any carlover.
It had great wheels and new Firestone 205/55 16" tyres, new discs all round and new pads, a great leather electric driver's seat, all of which have found their way into my '99 V70. All this including the engine & transmission for $950. Mind you it took me 1.5 days in searing heat to remove the engine/transmission assembly. What can I say, I'm a lucky man.

So how do you turn a 850 engine into a series 2 V70 engine? (with different head)

Well the accessory bracket from the '99 bolts right up with 5 of the 7 bolts are being used (the blocks were upgraded with 7 bolts from '99 on) I don't see it being a problem as the 850 only used 5 bolts and carried the same weight. I suspect the penalty will be increased vibration as the different design accessory bracket may require a greater number of bolts to avoid resonant frequencies. Perhaps this is how Volvo helped the later engines to be slightly smoother. Also the casting on the exhaust side of the block looks different with 2 large flat areas on the later motor.

The water pipe at the rear of the block is a different shape (or you can keep the old one and just run 850 lower radiator hose) It just pulls out; there is an O ring seal there but I kept the old o ring, hope I don't regret it.

The sump on the V70 has a inbuilt thread to carry a fuel line holder and the V70 sump bolts straight on to the 850 block. Another of the fuel line holders was behind the accessory bracket on the V70 motor but the 850 has no tapped thread there.

A helicoil to take a 8mm thread will have to be tapped in to the 850 block to accomodate the mechanical tensioner.

The hose from the block to the PCV box will need to be taken from the V70 and of course the '99 V70 PCV box itself is different.

The V70 only has one knock sensor in a more centralised position. (850s have 2)

The pistons in the '99 V70 share the same physical size as the 850s but the 2nd compression and oil ring are lower; no big deal.

The crank pulley has 21 teeth on both engines.

I'll post more pics as I re-assemble her. The head has to go in to a machine shop for a straightening and skim.

[SimLyons]

Just curious: Why change heads from the old engine with all that cash to repair it when the "new" engine seems really tight (based on your compression readings).

Also, how's it all coming along now?

[precopster]

You can't put a 93, 94, 95, 96, 97, or 98 head in a '99 V70/S70. TOTALLY incompatible through inlet ports, throttle system (drive by wire) and Denso engine management. The only likeness is the 4 speed gearbox.

'99 was the first year for the newer lower profile heads, ETM, and VVT for the turbos. 2000 saw VVT for the NAs as well as oil coolers mounted to the sump. These newer motors are almost identical to current motors 2001 through 2007.

I'm going this route instead of purchasing a used motor as it's far cheaper ($210 for the motor alone, plus machining/straightening of the ORIGINAL v70 head) and I get a good 20 valve VVIS head left over to build for another car (I have a spare 10 valve block which is about to be converted with 20 valve pistons)

I'm still waiting for my local machine shop to open after holiday break. I'm really keen to get this car going.

[precopster]

So here's some pics of the head when it came back and some pics of the new mounting points I had a professional welder add to the block for $140. I did my own tapping and threading.

I hope this doesn't stress the block later down the track, but I couldn't take the risk of running 5 bolts on the accessory bracket when 7 are required. I even managed to get the fuel line holder secured.

Today I'll be torquing the head bolts and fitting the cam cover.

[matthew1]

(These are precopster's photos, I'm just putting them up)

[precopster]

Did some more assembly today and popped the other hole in the cam cover to create a great cam hold down tool!! I used heavy duty zip ties and there was hardly any movement. A piece of flat bar with 4 holes drilled in it would have done the job too but it was so easy with this tool.

Patent is now pending