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Stopping tappet rattle
beachbuggy61 - December 24th, 2009 at 03:35 PM

Hi all, I hope you can help.
I have a 1641 t/p with a W110 cam and 1.25's and I can't seem to get the tappets to run quietly!

I've had varying advice; from "VW's always run 6 thou and never any other setting or you'll get valves riding", to "put up with it cos you've got a cam and it's part of life", to one place I saw that they recommended no clearance when stone cold.

I'd like to get it quieter if I can without sacrificing compression and/or riding valves.

Any advice?

Many thanks,
Marc

beachbuggy61 - December 24th, 2009 at 03:36 PM

Oh, and I've tried to search the Tech Talk forum subjects but no luck.

Thanks.

Bizarre - December 24th, 2009 at 03:54 PM

What have you got them set at now??

Do you know what sort of push rods you are running cro-moly?? or stock ??

vwo60 - December 25th, 2009 at 05:56 AM

HI, i have a 2054 running chromoly push rods and still run .006" tappet clearence, the best way to sent the tappets is to check them hot and work backwards to get the clearence that your engine likes, if the engine has .012" clearence hot then set the tappets to .000" cold so when the engine heats up and grows you will have .006", you must remember that the air cooled engine has no water jackets to quiten down the engine and will make more mechanical noise because of this.

OZ Towdster - December 25th, 2009 at 06:19 AM

Also check you are setting the tappets at the right stroke ie # 1 is at top dead centre , set number one , wind motor backwards 180 deg , set #2 and the same for 3 & 4 turning the motor back another 180 deg only between each cylinder

alien8 - December 25th, 2009 at 09:09 AM

A tappy motor is a happy motor!

I have no idea if this is true or not, I just like the saying:lol:

Joel - December 25th, 2009 at 11:19 AM

not to tappy otherwise they just pound away the top of the valve stem

ive always set bone stock twin port heads to 0.10mm/4thou and never had a problem. keeps them nice and quiet and not to tight. some manuals say 4 thou but some say 6 for T/P heads

Tighe cams recommend that the gaps for the model of cam i run in my 1776 be set at 8 thou for ex and 6thou for intake

different cams and ratio rockers seem to chuck stock specs out the window

Special Air Service - December 26th, 2009 at 07:28 PM

Quote:
Originally posted by OZ Towdster
Also check you are setting the tappets at the right stroke ie # 1 is at top dead centre , set number one , wind motor backwards 180 deg , set #2 and the same for 3 & 4 turning the motor back another 180 deg only between each cylinder


Whats the theory behind turning the motor backwards? Does it make any difference? or am I reading too much into your answer?

Cheers

Brendan

mackaymanx - December 26th, 2009 at 07:55 PM

It makes no difference if you go backwards or forwards, but it changes the order you adjust the valves in.

beachbuggy61 - December 28th, 2009 at 03:13 PM

Quote:
Originally posted by Bizarre
What have you got them set at now??

Do you know what sort of push rods you are running cro-moly?? or stock ??


Have them set at 6 thou at the moment, running stock pushrods.

Thanks.

beachbuggy61 - December 28th, 2009 at 03:17 PM

Thanks everyone. I've definitely been setting them at TDC for each cylinder using the "do #1 and turn it backwards" technique so I'm confident the settings are consistent.

Will check them hot and go from there I think.

Thanks again for the input, will let you know.... :)

beachbuggy61 - December 30th, 2009 at 12:51 PM

Wound up with 4 thou. Still a little tappy but much better than they were.

Thanks everyone for the advice.

Cheers, Marc.