Hello I have a 1973 datsun pickup truck with a ford 302 in it. I have an odd clattering under hard acceleration and when cruising in mid range rpm's It also does it when I let it slow its self down in gewar from higher rpms. I can get it to do it while parked and it doesnt sound like its coming from the valve covers I was thinking it could be lifters because it also does it only when its warm. thanks will
high mileage? Remember this is only my opinion based on my experience in a similar situation, but I think you are looking at a rebuild soon. It sounds like a similar problem I had in a similar engine, a 351Windsor. I had a E350 work van that had a zillion miles on it. The sound it made on acceleration was like the timing was too advanced and it was pinging. It would also make the noise at light throttle settings at cruise on the highway. I fiddled with the timing, replaced the distributor, messed with the vaccuum advance with no luck (because it wasn't what was wrong). It turned out the motor was just plain worn out. The rod bearings were so worn out I ended up stacking a rod bearing (when one half of a rod bearing gets under the other one. I did manage to drive it a hard 10 miles home before it went kaboom in my driveway. Man! You wanna talk about clattering! I pulled the engine (not as bad as you would think in a full size van) and I dropped the oil pan. You could wiggle the rod caps and they would clunk on the journals. In the early days it would only make the noise when it was up to operating temperature. Also watch for extremely low (blinking oil light) at idle. If your 302 has a lot of miles on it, you might want to consider rebuilding the bottom end. I replaced my engine with one out of a wrecked truck with a lot less miles on it. It was like a brand new van! I couldn't believe how worn out and powerless the old motor was. Tell us what you find. Good Luck!
Well I hope thats not it is there any way I can se if the lifters have maybe collapsed or have something wrong. I have 20 pounds of oil pressure at warm Idle and the oil is perfect. I dont know I am pretty puzzled? thanks again, will
If you have 20 psi at idle then its not likely you have the same problem I had. I wouldn't want to steer you in the wrong direction, but for a moment it sounded like what I had. A relatively easy task would be to pull the valve covers and check clearances. That might be a step in the right direction.
I already pulled the valve covers and I cannot tell if these rockers are adjustable there not like a buick but when I when to see how tight they were I couldnt tighten them any more I did pull a coulpe on both sides and the pushrods looked straight. None of the rockers were loose either. thanks, will
