M52 tapping noise

Post Sat Mar 23, 2019 1:17 pm

Hi,

Just finishing up my M52 swap and wondering if this tapping noise is most likely to be sticky injectors or noisy lifters?

I had the injectors sent off to InjectorTune a while back and they did come back with a note saying they could get stuck after a clean. I’ve given them a tap etc insitu but hasn’t made a difference.

Any ideas ?

Post Sat Mar 23, 2019 9:17 pm

Should also add engine hasn’t been run for at least 2 years since I removed from donor car.

I’ve read that overfilling oil by half a litre or so can help so might give this a go.

Post Sat Mar 23, 2019 10:58 pm

Could be the hydraulic tappets. There is a bleed procedure which is easily googled. Something like run it at 2k revs for 10 mins. Can't remember exactly.

Post Mon Mar 25, 2019 7:24 am

Also I realised I only put 6L of oil in, still have a 1L container left. I had checked the dipstick and it was between the marks so forgot to add any more after that. I guess the dipstick is now slightly incorrect due to the new sump?? I will chuck another half litre in and make a new mark on the dipstick I guess.

Post Mon Mar 25, 2019 7:31 am

I assume this is the bleeding process:

Firstly, get the correct viscosity oil, you will not cure the problem if the oil is too viscous.

The procedure is pretty simple and is designed to bleed the HVA elements:

Check the oil level, replenish if necessary. Run the engine at idle and listen for noisy tappets, if the tappets are noisy run the engine at 3000RPM (with the car stationary) for 3 minutes. Return the car to idle for 30 seconds (to achieve minimum oil pressure) and listen for noisy tappets. If a tappet is still noisy increase engine speed to 3000RPM again for 3 minutes.

It is possible that you may have to repeat this procedure 5 times to bleed the tappets correctly. If the problem persists there may be another problem but in most cases this will provide the cure.

Will give it a go and report back, cheers.

Post Mon Mar 25, 2019 7:38 am

Yeah that's the one. Worth a try to see if it gets any better.

Post Sun Apr 14, 2019 8:24 am

Did this solve the tapping

Post Sun Apr 14, 2019 1:48 pm

Sounds like injectors to me, although obviously not stuck because if they were you would have a missfire

Post Mon Apr 15, 2019 12:01 pm

I had a go at the bleed process yesterday but the noise really sounds like its coming from injector area, you can feel it with a hand on the fuel rail also. I had the injectors sent off to InjectorTune about a year or so ago for cleaning, they did come back with a warning that they could be sticky if not fitted straight away once the cleaning fluid had evaporated. Wouldn't they have spotted an issue with the injectors during the cleaning process if they were shot? This is first time running car on the injectors since being cleaned.

I think the noise was reduced once I had added more oil and ran a couple of bleed cycles. Still a little noise present though

Post Mon Apr 15, 2019 12:02 pm

I'll do another video when I next start it...got another issue at the moment though in that sump is leaking at join with transmission. Joy

Post Wed Apr 17, 2019 7:52 pm

I had an E36 328i come in last year for some work and it also had very noisy injectors, car had only done 40,000 miles too

Post Wed Apr 17, 2019 8:50 pm

Switch the ignition on and off a few times while listening to it. Injector noise will cease instantly, while tappets, or anything more ominous, will continue while the engine is still turning.

Post Wed Apr 17, 2019 10:33 pm

Thanks Brian, I shall give that a go and see what happens

Post Sun Apr 28, 2019 9:43 pm

Did the test Brian suggested and confirmed sound went away as soon as ignition was cut.

Took a punt on a new camshaft sensor and the noise has completely gone. Quiet as a mouse now so that was a result.

Now to just get the hydraulics sorted and I can think about driving the bloody thing!

Post Wed May 01, 2019 4:53 pm

joeyb wrote: ↑
Mon Apr 15, 2019 12:02 pm
I'll do another video when I next start it...got another issue at the moment though in that sump is leaking at join with transmission. Joy

Did you use sealant when you bolted the sump on?

Post Thu May 02, 2019 1:28 pm

Rinx wrote: ↑
Wed May 01, 2019 4:53 pm

joeyb wrote: ↑
Mon Apr 15, 2019 12:02 pm
I'll do another video when I next start it...got another issue at the moment though in that sump is leaking at join with transmission. Joy
Did you use sealant when you bolted the sump on?

Yes I did.

I've just installed a new sump gasket, this time without sealant. I've only had the car running for around 10mins on idle but so far so good, no leaking!!

Post Fri May 03, 2019 9:40 pm

Hopefully it will stay leak free!

I just checked the Bentley manual and it says to use sealant, however I think I will do a dry assembly like you have done. It would be useful to know how you get on with it.

Post Fri May 03, 2019 9:44 pm

If you use sealant on a sump gasket, use it very sparingly. Any that squeezes out inside the sump is very effective at blocking the filter mesh on oil pick up pipes.

Post Fri May 03, 2019 10:21 pm

Brianmoooore wrote: ↑
Fri May 03, 2019 9:44 pm
If you use sealant on a sump gasket, use it very sparingly. Any that squeezes out inside the sump is very effective at blocking the filter mesh on oil pick up pipes.

I think my issue was in my effort to use it sparingly I used it unevenly...probably opening up some gaps.

I'll update this thread once I've had the car on a proper road test. Just got to find some time to fit the second new clutch slave cylinder and get it bled up.

Post Tue Sep 03, 2019 9:33 am

Did fitting the gasket dry do the job Joey?

Post Tue Sep 24, 2019 11:13 am

Rinx wrote: ↑
Tue Sep 03, 2019 9:33 am
Did fitting the gasket dry do the job Joey?

Sorry just seen this, sure did! No leaks since. Lesson learnt!

Post Mon Nov 04, 2019 10:58 am

I think I have the same problem! Will try tightening the sump bolts slightly and see if that works. Did you manage to change the gasket with the engine in situ?

Post Mon Nov 04, 2019 2:46 pm

Rinx wrote: ↑
Mon Nov 04, 2019 10:58 am
I think I have the same problem! Will try tightening the sump bolts slightly and see if that works. Did you manage to change the gasket with the engine in situ?

Yes but needed to buy an engine support beam so I could drop the sub frame down and out of the way. Pretty straight forward though.

Post Mon Nov 04, 2019 3:23 pm

Cool. I will add that to the ever growing list of jobs to get done before I can get it on the road!

Just another quick question - did you use a 2 speed fan or single speed? I've used the auxillary fan from my donor car and trimmed it down so it sits nicely in front of the rad. Was thinking of just using the high speed setting triggered by the Ti fan switch at the lower of the two temps. Hopefully that will do the job.

Post Thu Nov 14, 2019 3:25 pm

I used E36 two speed aircon rad and wired in to use both high and low speed. Quite straight forward to do and a very satisfying job.

Post Fri Nov 15, 2019 10:15 am

Sounds good, I'm using the 2 speed aircon fan as well. I've knocked up a loom for a single speed fan but haven't hooked it up yet. Should be pretty easy to add some more wires to run the low speed so will probably do that.

I don't have a garage to work in so it looks like I will be making slow progress (if any) until the weather gets better!