A few basic maintenance questions

[Jay 535i]

What's the lifespan of the sparkplugs in the M30 motor? How do you know if they're worn out?

I'm replacing my cam cover gasket. Does it just go on, simple as pie, or is there some kind of grease/glue/whatever that goes on there, too? Do I need to scrape away anything before installing the new gasket?

When the spark plug goes into its hole, is there a washer or something there? If so, can that washer be reused?

Please excuse the novice questions. I'm trying to increase the amount of work I do myself, and it's really shocking (to me, at least) how little I know about the most basic tasks, like installing a spark plug. Especially considering my generally encyclopedic knowledge of cars. I've been reading about cars, well, since I could read, but never did anything more than change a tire myself. :)

Thanks in advance for the answers.

[Adnan]

Hi,

I believe the manual states a 30k mile interval. If this car is new to you and you don't know when they were last replaced, go ahead and replace them. It's easy and costs very little.

There is no separate washer for the spark plugs. New plugs come with a pre-installed crush washer. Make sure you use a dab of anti-seize on the threads and go carefully to ensure that the threads are not crossed. The plugs are easy enough but #6 takes a little patience.

The valve cover gasket does not use any kind of sealant. However, many will use a little on the front right corner (looking from the front of the car, facing the engine) as a slight leak seems to be typical.

If this car has an unknown history, consider a regimen of preventive maintenance - belts, hoses, vacuum lines, air intake bellows, brake/clutch fluid flush, gearbox and rear diff fluid change coolant change, etc. Most of these are easy DIY on the M30, which is a big reason I still have this car.

Oh, and get the Bentley manual, a must-have.

Hope this helps,
Adnan

[632 Regal]

I agree with everything except the antiseize on the plug threads, if used it will overtighten the plug and could strip the threads if torqued properly.

DO NOT EVER change the plugs if the engine is hot, you will gall the threads in the head.


Hi,

I believe the manual states a 30k mile interval. If this car is new to you and you don't know when they were last replaced, go ahead and replace them. It's easy and costs very little.

There is no separate washer for the spark plugs. New plugs come with a pre-installed crush washer. Make sure you use a dab of anti-seize on the threads and go carefully to ensure that the threads are not crossed. The plugs are easy enough but #6 takes a little patience.

The valve cover gasket does not use any kind of sealant. However, many will use a little on the front right corner (looking from the front of the car, facing the engine) as a slight leak seems to be typical.

If this car has an unknown history, consider a regimen of preventive maintenance - belts, hoses, vacuum lines, air intake bellows, brake/clutch fluid flush, gearbox and rear diff fluid change coolant change, etc. Most of these are easy DIY on the M30, which is a big reason I still have this car.

Oh, and get the Bentley manual, a must-have.

Hope this helps,
Adnan

[Felixdacat]

I don't know what brand of plugs guys use, but I have very good results running Bosch Plat + 4's.

[mamilapon]

Iwould use whatever is recomended in Bentley's- Do you have one? If not, buy one, you'll recover the money spent the first time you open the book to fix something on your car.Do not forget to check the two bolts that hold the oil spray bar under the rocker cover when you change the gasket ...Very important.

[Dave M]

I agree with everything except the antiseize on the plug threads, if used it will overtighten the plug and could strip the threads if torqued properly.

DO NOT EVER change the plugs if the engine is hot, you will gall the threads in the head.

Very good advice.

It states cleary in the BMW torque values document that plugs are to be DRY when installed. Seizing of a plug in an aluminum head in a well maintained vehicle should not be a concern.

Dave M

[632 Regal]

there are constant problems in running any other plug than is called for in your manual, last I looked plat 4s werent in there. You are one of the rare examples of no problems as of yet.


I don't know what brand of plugs guys use, but I have very good results running Bosch Plat + 4's.

[Alexlind123]

You will need a torque wrench and torque specs for this job. Use the specified copper plugs.

Oh, i almost forgot. Get a Bentley manual!!! These jobs are sooooo easy with the bentley manual and the proper tools.

[SRR2]

One more bit of advice: blow the dirt and debris out of the plug wells with your air gun before removing them. If there's a lot in there some can fall into the cylinder when you take the plug out.

[Jay 535i]

Thanks everyone.

I do have a Bentley manual, but thought I'd see if you guys have any good hints that aren't in there -- and you did :)

[Stacy (Sydney)]

Be careful not to overtighten the plugs - exsp' when using a torque wrench, ensure you have checked that the wrench is operating at very low torques first.( e.g. set to 20nm and have a go at a wheel nut). If not, you may find out when its too late with a spark plug. Happened to me, split the spark plug, a mechanic was able to remove the debris easily, I was lucky to get off cheap. Even better, get a feel for what is tight enough (i.e. experience).

Good call by another thread to watch number 6 spark plug ( closest to dashboard).

[GoldenEagleFan]

It's always a good idea to put spark plugs (in any engine) in by hand. This way you will feel any cross-threading immediately. Only the last 1/2 turn or so needs to be done with a torque wrench. I also agree, make sure it's a calibrated tool.

[Old F4 Pilot]

I use Bosch Platinum Plus plugs in my 89 (M20) engine and I have to change them about every 80,000 mi or so. My BMW dealer's service mgr. told me that under no circumstances should I use the Platinum Plus 4's because they'd do internal piston/valve damage in an engine as old as mine. I now have 305,250 miles on the original motor and I regularly run it up to redline (6200 rpm) , through the gears at least once or twice a week. The engine and automatic trans are original and still going strong.

[Old F4 Pilot]

I use Bosch Platinum Plus plugs in my 89 (M20) engine and I have to change them about every 80,000 mi or so. My BMW dealer's service mgr. told me that under no circumstances should I use the Platinum Plus 4's because they'd do internal piston/valve damage in an engine as old as mine. I now have 305,250 miles on the original motor and I regularly run it up to redline (6200 rpm) , through the gears at least once or twice a week. The engine and automatic trans are original and still going strong.

[Robin-535im]

Thanks everyone.

I do have a Bentley manual, but thought I'd see if you guys have any good hints that aren't in there -- and you did :)
I would avoid the Bosch Platinums personally... with all due respect to F4 of course... Bill R. posted recently about NGK iridiums and besides F4 I've only heard bad things about the Bosch Plat's.

HTH


Robin

[athflying79]

I used the +4's and ran great for about a month. Then every morning for the first five minutes it ran like it had a fouled plug. Swapped em out for the WL8 something or anothers and ran much better and smoother.