Changing front Suspension Springs

[Benengo]

The near side front spring on my 1982 BMW 635csi has broken and popped over the housing. I've found replacement part at a reasonable price from eurocar part and am considering replacing it myself.

My question is how hard a job is it to replace? I'm reasonable with a set of spanners but not experienced. Any ideas on how long it would take? I'm guessing it is essential to do both at the same time?

also if i do get a pro to do it how many hrs labour should i expect to do both sides?

Many thanks!

[WeirdNeville]

Benengo said:

The near side front spring on my 1982 BMW 635csi has broken and popped over the housing. I've found replacement part at a reasonable price from eurocar part and am considering replacing it myself.

My question is how hard a job is it to replace? I'm reasonable with a set of spanners but not experienced. Any ideas on how long it would take? I'm guessing it is essential to do both at the same time?

also if i do get a pro to do it how many hrs labour should i expect to do both sides?

Many thanks!

Yes, you should do both at the same time.
By "popped over the housing" What do you mean? Has it come downwards over the spring seat? Has it bent anyting else in the strut?

Assuming your 635 has strut front suspension (which all links I can find indicate that it has) the process is along the lines of:
Slacken the top mount nuts within the engine bay.
Lift car.
remove wheel, possibly remove caliper
Unbolt the strut assembly from the steering knuckle and remove the top mount nuts.
Remove the strut assembly from the car.

• SAFETY CRITICAL*

Use spring compressors to securely compress the spring and hold it. This and the following steps are tres dangerous rodney.
Loosen the damper nut that holds the top mount to the strut assembly, remove the top mount. (may require special tool)
Remove the spring, de-compress and bin it.
Compress the new Spring. DANGER WILL ROBINSON! DANGER!
Place where the old one dun did go paying attention to mount it correctly in the spring seat and top mount, it may have a specific orientation and direction to mate properly with the seating points top and bottom.
Replace top mount onto strut.
Tighten top mount bolt to required torque. (torque wrench required for anything to do with suspension).
Release spring compressors. Check you still have a face.
Refit strut and correctly torque all bolts.

Repeat for other side.

Bear in mind this is generic "how to change a spring on a mcpherson strut" advice, and NOT specific to your 635i. I think you could do the front end of a car in 2 days on a driveway, with enough time for swearing, loosening rusted bits and drinking tea. I did all four corners of my car a while back, and it's a rewarding job but there are tricky moments. Using spring compressors is not for the feint hearted, and you do need quality tools and a torque wrench.

Expect 4-6 hours labour for both sides, I reckon, although just phone the garage and get book time for the job as this is what they will most likely charge.

[eltax91]

With it having broken and slipped, not just a nibble from the end, I'd be inclined to garage it. They are dangerous as fk when they go off, they would take your head off. Like a coiled spring, you might say.

I did some when complete using pairs of spring compressors, and it was an awful job, just permanently worried about it firing off and hurting!

The second time, I took the whole McPherson assembly out as one, with the damper and top plate in place, then took them to the local garage to get them to use their proper floor standing spring compressor to do it. They charged me £20 for the pair.

[944fan]

Autodata says 1.1 hours per side.

[Cost Captain]

944fan said:

Autodata says 1.1 hours per side.

assuming this is for an experienced mechanic?

[WeirdNeville]

Cost Captain said:

944fan said:

Autodata says 1.1 hours per side.

assuming this is for an experienced mechanic?

That'll be book time, I'd imagine. Phone up and get a quote for your car specifically, that's the only real way of making your mind up whether it's worth your time or to pay someone.

doogz said:

WeirdNeville said:

Expect 4-6 hours labour for both sides

If the mechanic is a blind leper maybe!

What can I say? he's cheap, and I like to support the less advantaged.

My lower guess was 4 hours, not so far from the 2.5 that "book time" states for both sides.

[Benengo]

Right don't mind getting my hands a bit dirty but would like to have the same number of fingers/hands/limbs at the end of it. The local garage has quoted 2hrs a side at £35/hr which isn't 1.1 hr per side but not extortionate so think I'll have a chat with them.

Thanks for your help... I love Pistonheads

[redtwin]

I have done a few in my driveway with hand tools and £10 spring compressors and I would say 1 hour per side is more than adequate for someone who knows what they are doing and isn't wasting time trying to figure out what bolt to undo next.

I did the struts on my E46 about 5 or 6 times fitting new struts, trying out different springs etc and I could do both sides in less than an hour and a half (fasteners well lubed from previous works), but then I was going as quickly as I could as there were dark clouds rolling in and I didn't fancy finishing the job in the rain.

[WeirdNeville]

doogz said:

1.1 x 2 =/= 2.5

At least I actually tried to help the OP by explaining what the job would likely entail, rather than just ripping apart someone elses post.

3000 posts in 38 months =/= knowledge.

[Oldandslow]

One point I'd add if doing it at home and you're only lifting one side of the car at a time. Undo the anti roll bar link at the start and reconnect it at the end. Allows you to get full travel on the suspension to get the strut assembly in and out.

(Based on doing this exact job on an MX-5 so may not be totally applicable. Just to reiterate that handling a compressed spring is dangerous. Make sure compressors are secure and evenly tightened, when handling DO NOT get fingers between coils of spring, they can pop sideways and coils on inside suddenly close = lost finger(s). DO NOT point either end of compressed strut at your self or someone you're even slightly fond of, if the compressors let go large chunks of metal will most likely go in those directions = lost face)

[944fan]

Oldandslow said:

One point I'd add if doing it at home and you're only lifting one side of the car at a time. Undo the anti roll bar link at the start and reconnect it at the end. Allows you to get full travel on the suspension to get the strut assembly in and out.

(Based on doing this exact job on an MX-5 so may not be totally applicable. Just to reiterate that handling a compressed spring is dangerous. Make sure compressors are secure and evenly tightened, when handling DO NOT get fingers between coils of spring, they can pop sideways and coils on inside suddenly close = lost finger(s). DO NOT point either end of compressed strut at your self or someone you're even slightly fond of, if the compressors let go large chunks of metal will most likely go in those directions = lost face)

Best piece of advice so far. I learnt this the hard way, wrestled with that strut for ages before I realised why I couldn't get the git in the right place.

[J4CKO]

Its dead easy and safe if you use compressors, also crack the top nut whilst its still on the car, makes life easier !

Nothing like being chased round the room by a high velocity top mount to focus the mind

[Chiswickboy]

WeirdNeville said:

Benengo said:

The near side front spring on my 1982 BMW 635csi has broken and popped over the housing. I've found replacement part at a reasonable price from eurocar part and am considering replacing it myself.

My question is how hard a job is it to replace? I'm reasonable with a set of spanners but not experienced. Any ideas on how long it would take? I'm guessing it is essential to do both at the same time?

also if i do get a pro to do it how many hrs labour should i expect to do both sides?

Many thanks!

Yes, you should do both at the same time.
By "popped over the housing" What do you mean? Has it come downwards over the spring seat? Has it bent anyting else in the strut?

Assuming your 635 has strut front suspension (which all links I can find indicate that it has) the process is along the lines of:
Slacken the top mount nuts within the engine bay.
Lift car.
remove wheel, possibly remove caliper
Unbolt the strut assembly from the steering knuckle and remove the top mount nuts.
Remove the strut assembly from the car.

• SAFETY CRITICAL*

Use spring compressors to securely compress the spring and hold it. This and the following steps are tres dangerous rodney.
Loosen the damper nut that holds the top mount to the strut assembly, remove the top mount. (may require special tool)
Remove the spring, de-compress and bin it.
Compress the new Spring. DANGER WILL ROBINSON! DANGER!
Place where the old one dun did go paying attention to mount it correctly in the spring seat and top mount, it may have a specific orientation and direction to mate properly with the seating points top and bottom.
Replace top mount onto strut.
Tighten top mount bolt to required torque. (torque wrench required for anything to do with suspension).
Release spring compressors. Check you still have a face.
Refit strut and correctly torque all bolts.

Repeat for other side.

Bear in mind this is generic "how to change a spring on a mcpherson strut" advice, and NOT specific to your 635i. I think you could do the front end of a car in 2 days on a driveway, with enough time for swearing, loosening rusted bits and drinking tea. I did all four corners of my car a while back, and it's a rewarding job but there are tricky moments. Using spring compressors is not for the feint hearted, and you do need quality tools and a torque wrench.

Expect 4-6 hours labour for both sides, I reckon, although just phone the garage and get book time for the job as this is what they will most likely charge.

Excellent post which is really useful. Only one small point is that I would put the spring compressors on before taking the strut off and put strut back on car before releasing the spring.

The point some are making about a spring launching itself into space (through your face) is not really a problem if care is taken putting the compressors evenly on the spring and tightening them evenly.

Also some springs (early Fords) were quite short and even if the compressors broke the spring only opened up a few inches. Renault however were a different kettle of fish with R30 being about three foot long when taken off. I don't think that BMW ones would cause any problems.