Thread: noisy engine

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I have 1970 Ford truck with a 390 that has about 1000 miles on it. Bored .30 over .I recently replaced head gaskets in it. Truck runs strong except when it get up to temp my oil pressure drops and it starts to tick and make noise I removed both valve covers and listened to it run. Push rods are all tight the rocker shaft is on correct. I've heard that it could be bad cam bearings. Can someone give me some insight.

It's a stretch, but are you running a PCV, and do you have a breather on it? My running oil pressure improved significantly when I added a breather cap on one cover with the PCV on the other side (had only the PCV before, sucking vacuum on the crank case which was bad). I assume it's a flat tappet cam, right? If you can run it with the covers removed can you press down on the lifter side of the rockers one at a time and see if your "tick" noise changes? Any visible difference in the rocker arm movement from cylinder to cylinder? Wondering about a flattening cam lobe.

No the pcv was removed off of this engine I bought one last night to put on it I wont put on till this evening when I get home. If it sounds good cold and starts this noise when warm should I not be concerned that its a bad bearing

I don't see how a cam bearing could "tick". They can (and do) affect oil pressure, but there's too many support points for them to be contributing to a "tick" noise unless it's end play. IME there's a distinct difference between what I call a "tick" compared to a "knock". Lifter's "tick", while rod bearings "knock" and mains "clatter" or "chatter". If the PCV was removed then it must have breathers to relieve crank case pressure, right? Does your "tick" remain consistent, and follow rpm, diminishing as rpm gets up into mid-range?

Yes there is a breather on it its just a filtered oil cap. Once it gets to mid range and higher the noise fades away

Back in December you posted about a 428 and now a 390????????? so just what is the complete story???????

Its a different truck I have a 1970 f250 4x4 with the 428 and 2wd short box with the 390 the 4x4 is my daily driver. The shorty is a project I have been working on. I am quite partial to the 67-72 bump side ford trucks