New Engine Knock
 

Hey there,

I just got my 1915 turbo build up and running and have put about 50 miles on the engine. I'm running a deep sump, full flow oil filter, external oil cooler, the rockers are adjusted within spec. Within the past four or five miles or so, its started having what almost sounds like a rod knock and its blowing white smoke out the exhaust. My first guess about the white smoke was that it was that the turbo seals were leaking, so I took the wastegate off and it was blowing white smoke from the wastegate hole, which tells me that the oil is burning before the turbo. Ive been driving it easy to break it in and have only got on it maybe twice. I've checked the tolerances for the rockers like six times hoping that could be it.

Does it sound like maybe my bearings AND rings didn't seat correctly and Im going to have to pull the motor down and rebuild it or what? I'm kinda stumped at this point..

Oil Cooler?
 

Hi, you mention oil cooller, How far away and how large ID are your oil lines. Maybe after your road test, very soon after you get it home recheck for valve clearences. What are your oil pressures/cold and while driving? When you get on it, does the oil pressure go up as well? Lastly how the timing. Just something to check.

The oil cooler is under the passenger rear fender, not far at all from the engine and the lines are -8. The oil pressure was higher than I thought it should be, but I just figured it was because of the turbo, and it went up when I got on it. I don't remember exactly what they were though. I'll have to check out the timing next time I'm able to get out to the garage to work on it.

And for right now, until I figure out what it is I'm kinda hesitant to drive it. If I am going to have to do a rebuild, I want to try and keep the damage as limited as possible. I haven't driven it since I checked the clearances last time and it was making the knock as soon as I started it up..

turbo?
 

Hi, concernig your turbo. What oil resistrictor size are you running? The engine knock is that bad:eekno:, what rods are you running, and is the rod bolt and nuts stock? If the noise is that bad, hay just take the engine apart for safety sake.

I think its a .065 hole restrictor in -3 inlet line.. Sorry for the uncertainty, I started building this motor over three years, three different houses, and a trip to the desert ago so I don't remember some of the particulars.

I mean, the knock isnt THAT bad.. It just makes me nervous because knocks are never good and I have WAY too much time and money in this motor to blow it up..

I might just pull it down anyways. I have to pull the motor out to paint the engine bay anyways.

.065
 

Hi, well with a .065 oil restrictor, it rules out loss of oil pressue do the turbo. error on the safe side and take her apart, Good luck

Do you think its pinging?

It's not pinging it's actually running somewhere on the rich side. It's definitely some kind of a knock. I'm just not sure what type of knock it may be.

if your valves are adjusted correctly, then its probably a rod knock. what about when you push on the clutch does anything change? I was driving with a jacked up pushrod for a while and my engine sounded great lol, went to adjust the valves and yikes!! so i would doubt its valve adjustment. what about exhaust leak? sometimes they sound like a knock

What deck are you running? I had a mystery knock and smoke to sort out and it was a piston hitting, just the merest touch as it ****ed at tdc did it.

It doesnt seem like the piston is touching.. Ive turned it over by hand a million times and I would think that it would make it somewhat difficult to turn if it were.. I havent been able to work on it in like two weeks but Im tearing into it today and Ill let yall know what I find..

So, I got rid of the knock (permenantly I hope). I ripped it apart and was checking out the pushrods and one of them was slightly bent. I didnt think that could cause a knock like that, but I put in a new set of pushrods and its quiet as a mouse.. Its running great now, but its storming so I cant test drive it. But I had it running in the garage for a while.. I need to do a crankcase vent or something because it has like 75PSI of oil pressure at idle and like 110PSI when I hit the throttle..

congrats on fixing the knock!! but your high oil pressure isn't due to crankcase ventilation, what weight oil and what size oil pump are you running? also check your relief springs and pistons. your psi shouldn't be anymore than 50psi at idle when cold or 20psi idle hot, IMO