850 engine swap

[hjdlatd]

I have two 850 SE estates that I got from jhanani1 from here on the forums. Both are 1996 models, manual, one with B5202 engine (2 litre 10 valve) and one with B5204 (2 litre and 20 valve). I would like to transfer the 20 valve engine in place of the 10 valve due to the bodywork being excellent on the 10 valve car and only 140,000 on the 20 valve engine compared to 229,000 on the 10 valve. Is it a straight swap and ecu changeover. Can anyone confirm?

[surrey_man]

could you not just change the head and ecu ?? surely the blocks the same :?:

[dinky1]

Originally Posted by surrey_man

could you not just change the head and ecu ?? surely the blocks the same :?:

If he knew that he wouldn't be asking! There is also little point taking both heads off and testing because then you're in new head gasket, cambelt, tensioner, water pump territory.

[Darth Vol]

ideally speaking - and from what I've learned through my own recent engine loom conversion.... replace engine, engine loom and respective ecus' = no issues should arise later.

not as difficult a job as you might think.

thing to remember is that you:

• need to remove the dash top, dash clocks, and undertray from drivers side.
  
• then unlock the yellow, red and white connector blocks and 2/3 small connectors under the drivers foot well as well as the yellow/green 2 wire block connector that mates to the alarm relay.
  
• then remove the scuttle panel, and wiper arms (13mm socket) and using a 10mm socket remove the 4 10mm bolts that hold the general fuse and relay box to the bulkhead.
  
• then when the 4x10mm bolts are removed, remove the surrounding engine loom sections from drivers and passenger side and pull the relay box up and out.
  
• fitment of the replacement loom is the opposite as decribed above.
  
• It is possible however, at the ECU box end, to remove the engine loom section only from either engines (remove ecu) and pull the metal plate sections apart, and remove the engine loom (white) block and transfer looms across but not guaranteed to work as the 10v loom may have different wiring sequence.

Still, that one with 140,000 will still need it's 2nd timing belt so if that hasn't been done, get it done while engine is sitting out of car.

Handiest would be to drop the engine/gearbox out along with the subframes and swap across. Means you only have to deal with the engine top mount and the bolts securing the shocks to the bulk heads, and to the chassis. Swap the lot across as the dampers etc with the 140,000 would have longer life left than those with the 200k plus +

[surrey_man]

Originally Posted by dinky1

If he knew that he wouldn't be asking! There is also little point taking both heads off and testing because then you're in new head gasket, cambelt, tensioner, water pump territory.

Arh yes good point there but to be honest if your gonna do a engine swap
I would personaly do a cam belt drive belt water pump dizzy plugs ect change
it makes sence and easyer while the engine is out the car

[david philips]

just a thought but is there any thing wrong with the 10 valve engine reason i ask is some well maintained engines with say over 200k may be a better engine than a badly maintained one with only 100k.

unless you really want a 20 valve engine or theres something wrong with the 10 valve then why go to all the work changeing then over.

i am not saying theres anything wrong with either engine or even wanting to change them over.

[hjdlatd]

Thanks for all the replies so far. As I also received a load of spares with the cars I would of course be replacing the cambelt, tensioners etc. I have not inspected to hard but I do believe the 10 valve engine is leaking oil from the cam cover. I will investigate further as I am hoping it only has a blocked PCV. I suppose the slightly better economy of the 126 bhp 10 valve engine would be an advantage. Got the T5 or T4 for power when i need it, lol.

I will be transferring an LPG system from my current daily runabout, B2525 10 valve engine with 260,000 on it to whichever engine I end up keeping. I have loads of new parts that came with the car to swap over as well so I have my work cut out for me.

Again thanks for the replies.

[dinky1]

Originally Posted by hjdlatd

I will investigate further as I am hoping it only has a blocked PCV.

The PCV itself might not be blocked. I changed mine last year thinking it was blocked and when I got it out the thing not only weight the same as the new one but you couldn't see the slightest bit of sludge at the openings.

What I did find however, was a whole load of sludge in the hole of the engine where the bottom of the PCV unit fits into the engine. It was absolutely disgusting! In essence, it was the PCV part of the engine but just not the actual PCV!