How to change engine mounts

[redboy]

Some parts of 240's are lovely to work on- changing the RH engine mount is not one of them. This rubber part sits below the oil filter and gets soaked in oil. Mine wasn't broken, but it was 'squished' and sagging at a 45 degree angle- I could barely get my oil filter wrench around when changing the oil, and the engine was bouncing all asundry- I could sometimes hear the fan clicking on the shroud, and my exhaust kept blowing from the stress and banging. Definately time for new mounts.

The Haynes manual makes it look easy but leaves out some important tricks.

Here's my process- I'm sure others can refine this, and probably can add more:

1. remove oil filter- you need to do this to gain access to the bolts
2. disconnect battery cable and remove alternator- I've heard some people have changed it with the alternator in place, but I couldn't figure out how to get spanners in there. Also, move wiring harness out of the way so it doesn't get tangled up in the spannering or worse crushed in the mount.
3. place a jack under the engine sump- mine has a large rubber pad, but if yours doesn't, use a wooden block to spread the load.
4. support the engine- raise jack just until you see the engine lift a wee bit.
5. remove top and bottom bolts on rubber engine mount. The bottom one is a real pain, as the steering box makes it difficult to get a spanner in there. You have to turn it 1/4 turn at a time.
6. remove the 'front bottom' bolt on bracket holding the engine- it will foul on the engine rubber, so just undo it until you can feel its free- you probably won't be able to remove it entirely. Do this first- you don't want the trickiest bolt to be the one holding all of the weight in case the jack falls.
7. remove other 2 bolts- just before they 'go,' double check the jack and raise the engine a bit more to make sure its holding the weight of the engine. Be ready to move your arm- don't reach between the manifold and the wing just in case.
8. when all bolts are out, raise the engine slightly- you should be able to jiggle the mount and bracket out.
9. screw new mount loosely onto top mounting bracket. Install 'front engine bracket bolt' loosely into hole while out of the car- its easier this way.
10. Now to put the new mount on: Jiggle mount/bracket until you get the bottom screw on rubber mount through the hole in the lower bracket. Before you do anything else, start to thread the bottom bolt on while you have some play in the mount. Once its down, it tends to foul on the steering box and is much more fiddly to thread.
11. Jack up engine slowly until holes on engine line up with bracket. When lined up, screw in bolts by hand. Use spanner to tighten up. This is the nasty bolt that you can barely get your spanner on and only turn 1/4 turn at a time. A shorter spanner might make this easier and give you a few degrees more spin.
12. Tighten bottom bolt on rubber engine mount, making sure locating pin is in the hole.
13. slowly lower engine, letting mount take the weight. The locating pin should line up perfectly in the top bracket. Tighten top bolt.
14. reinstall alternator, connnect wires and battery cable
15. install new oil filter.


The other engine mount is so much easier as its on the other side of the 'slant' of the engine. The process is generally the same: support engine; remove bottom mount bolt; remove 3 engine to mount-bracket bolts. Jack up engine a bit to wiggle it free. When apart, separate rubber mount from bracket and install new mounting- tighten the bolt fully between the top bracket and rubber mount BEFORE installing on car.
Reinstall mount into hole on lower bracket; finger-tighten bolt. Lower engine and reinstall bolts between bracket and engine. Tighten everything up. Remove Jack and inspect everything to make sure it all looks as it should.

I didn't jack up the car, as I could get to everything better from the top than the bottom. Jacking the car up would only mean you have to lean farther to get to everything- also, when jacking the engine, it slightly raises the car too- you don't want to be de-stabilising the car from the jackstands when doing this job.

Have a torch handy- even on a sunny day, its hard to get light under the manifold where all of the bolts are.

The right side will take 1.5 hours of fiddling and the Left side about 20-30 minutes!

Why didn't they put the oil filter and alternator on the OTHER SIDE of the engine where there's all that space??

cheers,
Brian

[MazakMan]

Wow, that's the hard way to do it.

I always unbolt the lower alloy bracket from the crossmember and remove both alloy brackets and the rubber mount as one piece. Then change the mount and refit.
Never needed to take the alternator off either.

Isaac

[redboy]

How do you get the top bracket off without removing the alternator? Or do you leave the top mount in place and just jack up the engine more?

I always figured there's an easier way to do everything!

[MazakMan]

Originally Posted by redboy

How do you get the top bracket off without removing the alternator? Or do you leave the top mount in place and just jack up the engine more?

I always figured there's an easier way to do everything!

I think there may have been several wobble bars and U-Js involved - it was a while ago - but I definately didn't remove the alt and I definately got the mount assembly out as one piece.

I'd go and look now but there's only a bare shortblock sat on blocks of wood in the engine bay, so that won't tell me anything!

Isaac

[Paul240480]

Mmm, this is something that is on my 'list of things to do'. Mine look okay, but the engine is defo' a tad on the 'wobbly side' on tick over..............

One for the summer methinks..........

[redboy]

Yes- doing it in this biting wind and fading light was definately not my best decision.

[jetronic63]

I was told the diesel engine mounts are a bit stiffer if you want to reduce the movement on your engine - although the standard ones are OK when they are fresh.

[redboy]

I heard that too- I just got the £2.50 scan tech jobbies- I know they're not the best. I've actually heard that the GT Turbo mounts are the strongest- which is what I want for when these go.

cheers,
Brian

[classicswede]

The derv mounts are the stiffest ones. The scan tech mounts from my experiance tend to be short lived but with saying that I'm going back a few years so they could be better.

I'm going to be doing poly 240 mounts soon which are ideal as oil does not affect them.

[redboy]

I'm not too optimistic about the scan tech lasting very long- they're made in China and felt quite soft for being new. At least they should last long enough until your poly mounts are done!

I've thought the mounts are quite undersized for the weight of the engine- my Allegro's are three times the size- big rectangular things, with hydraulic dampers, and the engine probably weighs a third with a third less torque than the volvo.

cheers,
Brian