PR4/A oil filter housing cap thread - a thread thread!

b'knighted

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VOC Member
Here's a simple question for those who know and I realise that I could go and unscrew one to measure it to find out, but can anyone tell me if the thread on PR4/A oil filter housing cap is parallel or tapered?
 

roy the mechanic

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VOC Member
K T B gives it 2 1/4 x 20 tpi, no mention of taper. the example i'm building screws in home by hand, so I figure it has to be parralel.
 

riptragle1953

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There is no taper on this thread: now I've made it over ten words long so I can tell you. Who makes up these rules? What's wrong with a short message?
 

nkt267

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I think you will find that the taper behind the thread seals against the taper in the crankcase aided by a sealant as Roy has already posted..I think you may have misread Ian's reply.. John
 

riptragle1953

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Non-VOC Member
The straight threads tighten the cap with a tapered male flange against the case with an exactly matching female taper.... and no, a not-setting sealer is fine but most times unnecessary. ( uh, is there something difficult here to understand?)
 
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