Oil Leak
beachbuggy61 - April 12th, 2010 at 10:23 AM
Hi all,
I'm having oil leak trouble with my 1641. It's leaking around where the oil pressure switch goes. The thread was shot and so I rethreaded a slightly
larger hole and use an insert (brass) which the pressure switch goes into. Probably not ideal I know, but I was wondering if anyone knows of any
'wonder-stuff' that I can put on the thread perhaps to help with the problem? I'm not in a place to be able to afford a new engine case at the
moment! 
I've tried to tighten but am scared of stripping the larger hole!
Any help would be appreciated...
Marc.
Bizarre - April 12th, 2010 at 10:41 AM
mmmmmmmmmm................ i dont believe that thead is a parallel thead.
99% sure it is slightly tapered
Not sure what might have happened when you tapped it??
Is the brass one tapered??
The case hasent cracked has it??
barry
Sides - April 12th, 2010 at 10:47 AM
Hmm... maybe some teflon thread sealant ???
NOT the white teflon thread tape that plumbers use, but white grease like stuff that comes in a stick... mainly used on tapered pipe threads (NPT
etc.), and will stand up to oil no probs but at the same time any that gets into your engine won't cause issues. The one I have is Loctite brand,
from Repco, but other companies do it too (Permatex etc.)
Could also try red silicone, but I'd go the teflon sealant first... I don't imagine that little globs of silicone getting around in your oil would
do very nice things...
beachbuggy61 - April 12th, 2010 at 11:03 AM
Hi Barry, Have checked the case and it's definitely not cracked, thanks goodness! Yeah the tapering thing confuses me a bit. The brass fitting that I
put in (in the recut hole) is not tapered as far as I can tell - run the verniers over it etc - but the leak does appear to be between the brass and
the case, not the brass and the oil swith inside it, if you know what I mean!
Thanks Sides, I'll look down at my local Repco.....
greedy53 - April 12th, 2010 at 05:50 PM
vw do not have a tapered thread it's a common mistake to put tapered senders in as it will force open the hole the more you screw the sadder it gets
.nearly all cracks from the sender are a result of this little tapered thread being put into a non tapered hole
68AutoBug - April 12th, 2010 at 11:37 PM
| Quote: |
Originally
posted by beachbuggy61
Hi Barry, Have checked the case and it's definitely not cracked, thanks goodness! Yeah the tapering thing confuses me a bit. The brass fitting that I
put in (in the recut hole) is not tapered as far as I can tell - run the verniers over it etc - but the leak does appear to be between the brass and
the case, not the brass and the oil swith inside it, if you know what I mean!
Thanks Sides, I'll look down at my local Repco.....
|
I use loctite pipe sealant on My threads on the brass bit and the senders.. never had a leak... never cracked anything either.. lol
many people don't screw the oil sender in far enough when they know its a tapered thread... so they leak..
a bit of loctite on a clean thread will stop the leak...
cheers
LEE
PS: I used to use PTFE tape but didn't like the way it shreds..
-
vwo60 - April 13th, 2010 at 10:32 AM
Hi, i work with hydraulics all the time and the best sealant that i have used is loctite 577, it's a high pressure hydraulic sealant that does not
set solid, you normally prime the parts to be sealed with the appropriate loctite primer but you can degrease the parts with thinners as it is
important that there are no traces of oil on any components
Thinker - April 25th, 2010 at 11:35 AM
| Quote: |
Originally
posted by greedy53
vw do not have a tapered thread it's a common mistake to put tapered senders in as it will force open the hole the more you screw the sadder it gets
.nearly all cracks from the sender are a result of this little tapered thread being put into a non tapered hole
|
sorry greedy53 it is a tapered thread as quoted in the bently manual for installing pressure switch "taking care not to damage the tapered thread by
using too much force to screw in the switch. the thread acts as a seal."
as it turns out i pulled mine out yesterday a some one has put a parrallel threaded plug in and it has damaged the lower part of the thread.
part of the problem is that the pressure switch has a large hex so poeple will use a large spaner and over tightern it.
as for repairing it you would need to go over size and fit a reducer. it would need to be taped to 1/4 NPTF and use a 1/4 NPTF to 1/8 NPTF reducer.
A simple rule of thumb for installing tapered
pipe threads, both metal and plastic, is finger tight plus one to two turns with a wrench. Torque installation values
can be determined per application, but due to the variations involved in pipe joints such as disimiliar materials of
male and female threads, type of sealants used, and internal variations in product wall thickness, a standard torque
specification cannot be generically applied .
and a good sealant always helps.
hope this helps.