Stripped Pressure Switch Port

[NickPov]

Hi everyone. New here but finding the forum extremely useful! recently purchased an 89 1.9DG. It had a known BOD fault and I’d seen that it had a white “high” oil pressure switch fitted instead of the grey. I changed it out and also planned to change the “low” blue at the same time. Oil pressure had been checked and all OK. Tightening up the low switch I thought I started to feel the threads strip but wasn’t 100%. I stopped and it seemed to have sealed. I took it for a short drive and no signs of leaking. Today I’ve done about 100 miles with regular checking and no leaks. My questions is do you think it’s ok to continue to monitor for leaks or should I take it out and get the threads repaired? Thanks

[King Kenny]

It is difficult to say. My opinion is 'if it ain't broke, don't fix it'. Keep an eye on it, but if it gives you concerns then investigate further.

[Mr Bean]

No problem with leaks as you can spot them under the van. But should the switch blow out completely on the  road you could lose your total sump contents in a fairly short time and damage your engine if you never spotted the low pressure oil warning light coming on.  

I don't see what engine you have but in my case - a 2.1 WBX, I believe that if the high pressure switch went open circuit at over 2,000 RPM,  for instance by loosing the ground connection via the thread if the switch blew out, then the alarm would sound and save the day.

Whatever you do you should be ready to have quite a faff repairing  that  thread - probably not a ten minute job. Tricky decision .

(After my iffy 2008 rebuild  I found when I replaced the engine recently , that the high pressure switch lead had been grounded thus over riding that valuable safety feature.) (Surprised it lasted so long ) 

 

[NickPov]

Thanks for the replies.

I’ll continue to monitor it for now.

Mr Bean - I’ve got a 1.9 DG with the same warning system.

[silverbullet]

If you arw lucky, you might have 40 psi oil pressure. But the area of the end of the switch is about 1/8 of a sq inch, so thats all of 5 lb force trying to push it out of the threads...

[NickPov]

Silver Bullet, that was line of thought too. On the worst case 60 PSI I calculated there to be around 25-30N of force on it, so even with slightly damaged threads it still should be well below the force required to completely strip the threads and chuck the sensor out. I'll continue to keep an eye on it though.