When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
when I first read this I thought of the noise my truck makes from time to time....I only hear it when the truck is at idle and i am under the hood...drop three marbles in an empty metal coffee can and spin it around..that is what I hear....spray some wd40 on the belts and it goes away....Idler pully? PS pump? Water pump? Guess I won't know till something breaks
Mine makes this noise. It's not real noticeable unless you're under the truck, then it's loud. My brother (that built the motor) says it's rod side clearance, and not to worry about it.
when I first read this I thought of the noise my truck makes from time to time....I only hear it when the truck is at idle and i am under the hood...drop three marbles in an empty metal coffee can and spin it around..that is what I hear....spray some wd40 on the belts and it goes away....Idler pully? PS pump? Water pump? Guess I won't know till something breaks
I hear that sound, marbles being spun in a can, but I haven't worried about it. I am, however, concerned with the marbly knock. It is soooo noticable at idle. If I play with the gas and let off, as soon as the engine levels off at idle, I can hear that sound after about a second. And you know how the engine kinda lopes, the marble knock coincides with it. Anybody feel like making a trip to Lower Alabama?
Typically you want to make small changes in oil viscosity, and use the lightest that works good. You can scuff pistons with too thick of oil, as well as spin bearings on a cold day. But if your engine is old and worn out, a little thicker oil is just the thing.
My 2004 Baja boat with Mercruiser EFI 305 - 260 hp needs heavy oil. Mercruiser says to use straight 40w oil...or Mercruiser multi viscosity 15w40. Using synthetic will void the warrantee...Go figure. Tough...there is Moblie 1 in it. Oil is cheap...engine rebuilds are not. The Honda, on the other hand recommends synthetic oil...also requires a heaver oil. It gets Mobile 1 also. This confuses me considering these two machines typically run cooler than my truck, or any automobile for that matter. The Honda not only runs cool, but typically rich, due to the factory fuel injection mapping. I ran 20/50 in my Chevy S-10 for years ( summer time ). The 4.3l had 170,000 miles on it when I sold it and I know the guy I sold it to ran it well over 200,000.
Well, I'm getting concerned, the more I hear the knocking, the more nervous I get. The engine is a new rebuild and I know the heads need worked. I'm going to try the 10w40 oil tomorrow and see what happens. When I'm at hot idle (just got home from work, out riding around), my oil pressure is 10psi. Maybe bringing up my pressure will help. Let me ask you this...IF this oil doesn't take away the noise, I'm going to drop the oil pan. What will I be looking/feeling for?
Why is the oil pressure so low? Was the engine assembled with the wrong main bearings? 10 pounds of oil pressure will cause knocks!
Actually, from what I have seen on this and other forums, 10psi hot idle on an FE is not abnormal. The more important question is what is the pressure as the rpms come up to operating range, say 3000rpm? Rule of thumb is 10psi per 1000rpm.
Actually, from what I have seen on this and other forums, 10psi hot idle on an FE is not abnormal. The more important question is what is the pressure as the rpms come up to operating range, say 3000rpm? Rule of thumb is 10psi per 1000rpm.
I really still think it's rod side clearance. I would get a 15w40 instead of a 10w40, the 15w40 is diesel rated and is therefore a much more robust oil than a 10w40. It does other desireable things like keeping rings clean, cleaning sludge, has higher acid neutralization capability, and more anti-wear additives. Shell Rotella is a good oil.
My 360 idles hot with about 8psi, and I've never had a problem. Low oil pressure at idle is the norm for FE's with stock oil pumps. Doesn't hurt anything. If it gets below 5psi I'd get worried. You're probably losing pressure through the rocker arm assembly.
I really still think it's rod side clearance. I would get a 15w40 instead of a 10w40, the 15w40 is diesel rated and is therefore a much more robust oil than a 10w40. It does other desireable things like keeping rings clean, cleaning sludge, has higher acid neutralization capability, and more anti-wear additives. Shell Rotella is a good oil.
My 360 idles hot with about 8psi, and I've never had a problem. Low oil pressure at idle is the norm for FE's with stock oil pumps. Doesn't hurt anything. If it gets below 5psi I'd get worried. You're probably losing pressure through the rocker arm assembly.
I've got the heads restricted. If it's rod side clearance, what does that mean to me? Is that something that needs to be fixed?