Tappety M20B25

[richard300]

So, looks like i might get time to head over to my friends where i am storing the e30 i bought a couple of weeks ago.

When i drove it, it was VERY tappety, not rattly, not knocking, just that heavy sewing machine noise...

My friend whom i bought the car from told me the valves need adjusting before i went to look at it, and having done lots of reading and coming to the conclusion that these things can be very tappety. I want to know......

If after doing all the valve adjustments (gonna use the Wiki link and my brother has all the correct tools) and its still tappety (loud) what are my other options to help reduce the volume level of the tappety noise?


Is there an engine oil alternative?

Does changing the oil spray bar help? (sorry if thats a dumb question)

would upgrading the sound deadening on the bonnet help...i.e Dynamat?

I love the sound of the car with its scorpion exhaust but there is no way i'm going to enjoy driving it so much with the incessant tick, tick, tick, tick.....

[Grrrmachine]

Bear in mind the oil you're using probably isn't suitable for the sort of temperatures you're experiencing, and you'll get a proper clacketty noise from the top end. The oil spray bay can be changed, but it can also be removed (carefully) and cleaned in petrol as a quick test.

Do the valves when absolute cold, remember.

[shaun_89]

The tappet noise can be louder in the cabin than from outside on these.
It sounds wierd but the sound seems to travel up the steering column, if you put some bluetac over the steering wheel bolt at the end of the column it sounds much nicer from the drivers seat.

[hongkongfuey]

Im only up the road from you, if you want to pop down ill have a look

[richard300]

Thanks, for the extra info guys and offers of help.....

Hopefully she will sound far less tappety (from the outside of the car) when we are done....

Yeah, Portsmouth is not to far from me at all, when i get her road legal (Only requires insuring) for the late spring i'll no doubt be over your way at some point as often visiting Gunwharf and the Eastney Cruising Association Club.

[Kedge]

Aren't the injectors often responsible for the ticking noise?

[clipper]

Yes, but quietening down the valves makes a big difference.

I had to "bodge" mine because I realised that the top of the valve stems were concaved through wear and tear so the gap measured by the feeler was actually smaller than actual gap that the excentric had to close in order to start opening the valve.

In effect I discovered that setting my gaps at 0.25 with a feeler was actually allowing a 0.265 - 0.270 gap for the rocker / excentric to close.

I compensated for this by finding the lever ratio of the rocker arm, then calculating what the corresponding gap at the cam would be and setting the gaps there where the concaved wear had no effect.

This quietened mine down quite a lot, runs better too. The better fix would of course have been to replace the valves but I couldn't be arsed.

[richard300]

wow.... at £350.00 and upward for a set of new Injectors, i hope they are not the route of the problem.

[Kedge]

Even a refurb is no guarantee to shut them up. They're not faulty it's just something they do, so I've been told.

[capri_rob]

You dont need new injectors. A refurb at injectortune is £66 inc return postage. Well worthwhile.

A new spraybar may quieten down the top end - or you can do what I did and remove it, use a 1.5mm drill to widen the holes slightly which will increase oil flow and then flush it through with brake cleaner or petrol to remove any built up crap ( Tape the spray holes up and then undo them one by one to clear both the pipe and the holes ).

If the rockers are worn out though they're about £12 each for Febi bilstein ones from GSF - but then you're starting down the head rebuild route and into the full realms of "whilst its in pieces" jobs which will end up costing you the thick end of £500.

[Tom_Maverick]

I did my tappets last week, makes a massive difference, did the spraybar a month back too and that helped.. my M20 is now near silent and goes like STINK! if you want any advice do ask.. I used the pelican technical article.. just google it!

[richard300]

Thanks chaps..... Nice to know that the injectors can be refurb'd for a good price.
Did'nt have chance to visit the car this weekend as my wife was on call and typically was called out. No rush though don't plan on using the car for at least another month.

TBH, even if i did have to throw £500 at the engine it wouldnt be the end of the world as i got the car at such a good price.

I'll update when i do get onto it.

Thanks T_M I'll check out the pelican article.