92RS_Ttop

iTrader: (3)

So I finally got around to pulling my engine to fix the knock it developed a while back. I pulled the intake and carb to make pulling the engine easier, and after I got it out I found that the knock was simply a bent pushrod Other than that, the engine looks brand new inside, which it should since its only got 3-5k on it since I built it.

Problem is, I didnt drain the coolant completely because I thought it was a rod knocking and had planned on just replacing the engine with the one in my truck before i scrap the truck. So now I've got some pretty milky oil. I really don't want to do a full rebuild on it, and I'd prefer to reuse this engine since the one in my truck has a lot of miles on it and the oil pressure is kinda low. The engine hasn't been turned at all since I pulled it and slopped coolant all through it. Is there a way I can save it without tearing it the rest of the way down?

All the gaskets were in great shape, so I know the oil was contaminated when I pulled the engine, not before. I already pulled the oil pump and started cleaning it out. I was thinking I could maybe put it back in and use a priming tool and clean oil to flush the rest of the contaminated oil out of the oil passages? Or is this just wishful thinking?

ex-x-fire

Flush it w/ cheap oil right away, then change the oil/filter after you had it running 20-30 minutes.

92RS_Ttop

iTrader: (3)

Yeah, I was planing on running it for a little bit and then changing the oil and filter. I figured another change after the first 500 or so miles as well. Basically treat it like a fresh rebuild to make sure it will be ok.

TTOP350

iTrader: (8)

You need to find out Y you have a bent pushrod b4 you put it back together and also if it bet a valve or not..

92RS_Ttop

iTrader: (3)

The valve appears to be fine, but i haven't pulled it yet. Both the valve and the piston show no signs of contact at all, so i dont think the valve is bent.

As for why it bent, the 2 most likely reasons are that either I had the valve lash too tight on it or it was weak. I reused a set of old pushrods that I got with the engine. I checked them all for straightness by rolling them on a flat surface, but I could always have missed a slight bend in one of them.

I had also been messing with the distributor timing, trying to get a few more degrees out of it, and the engine started pinging a day or two before this happened. I don't know if its related or not.

92RS_Ttop

iTrader: (3)

Looks like I've got worse problems than I originally thought. When I drained the oil pan after getting the engine out of the car, the first quart or so came out looking like chocolate milk. The rest came out looking like oil. I pulled the pan and its got a nice layer of milky sludge in the bottom. I pulled the #2 & #4 main caps and found some more milk under them. Not much under #4, but #2 had it down in the crank oil hole as well. The bearings also show some pitting and scoring right by the edge where the 2 halves meet.

The head gaskets are not blown or damaged in any way, they came out easily and look almost new. I haven't checked all the cylinder yet ask haven't turned the motor by hand at all, but the bores I can see do not appear to have any cracks in the walls. A preliminary check of the heads shows no cracks there either. I did notice some oil in the coolant when I drained it, but didnt think much of it at the time as it wasnt a lot.

At this point, I'm not sure how else the coolant could have gotten into the oil? Any suggestions would be appreciated.

TTOP350

iTrader: (8)

bad intake gasket, head gasket or a crack in the head, block or ??

92RS_Ttop

iTrader: (3)

Those were my thoughts as well. Intake gaskets look brand new. I suppose it possible i didn't have as good a seal around the water jackets as I thought I did, but I used sealer on both sides of the gasket on all the ports.

As for cracks in the block, I did find some lines that could be hairline cracks on the walls of the lifter valley near cylinders 2,3,4&7. I'll try to get some pics posted up.

92RS_Ttop

iTrader: (3)

Taken with my cell phone, but you can see them pretty well. They wont wipe off, not sure what they are from, but could be cracks i guess.

92RS_Ttop

iTrader: (3)

Wow, it's been a long time since I updated this thread. Finally got everything back together and went to start the engine for the first time today. Primed the oil pump for a good 5-7 minutes first, got good oil pressure(60 psi on mechanical gauge). Put the distributor back in and it fired right up but wouldn't idle. Realized the choke plate on the carb was open all the way(manual choke), so i closed it down to where it should be.

Little harder to get it started this time, but it started and idled good. Idle was a bit high, but nothing serious. I don't have the tach wire hooked up yet as the wire connector for the coil is bent, but it wasn't over 2k.

Went to check the timing and noticed a knocking sound coming from the front of the engine. When I turned the timing light on, I couldn't see the mark on the balancer at all. I do have a dial back timing light, but didn't think to adjust the ****(was set at 0*). I can see a little over 90* of the cranks rotation looking at the tab and couldn't see the mark on the balancer anywhere.

Thought maybe I had the plug wires off by one tower on the distributor, so I shifted them around. Car wouldn't start at all then. So I moved them all back to their original positions, now it still won't start. Battery is getting close to dead now, so I'm letting it rest while I post this. I'll try it again when I'm done with this post, but will probably have to put the charger on it for a while.

I'm thinking my timing is way off, but didn't think it would run it if was as far out as it appears to be? And would that account for the knocking(detonation?).

The other possibility I can think of for the knock is the balancer/crank pulley. I thought one of the pulley bolt holes was stripped as the bolt wouldn't tighten, but I ran a tap through it and it seemed to tighten down ok. I didn't crank down on it real hard though.

Any thoughts or ideas would be appreciated.

92RS_Ttop

iTrader: (3)

I should probably mention that there was no play in the rods or mains when I tore the engine down and all the bearings were replaced with new, except for the cam bearings. I'm also not seeing any signs of coolant in the oil yet but it's been run for maybe 5 minutes so far.

92RS_Ttop

iTrader: (3)

So just to update with what I've found so far:

All 8 spark plugs have 1 or 2 small nicks on the ground strap on the side that is facing the valves. The straps are also pushed to the side slightly, in what would be the direction of the piston when installed. So I'm guessing the knocking I was hearing was the valves hitting the plugs. Never had this problem before I tore the engine down, so I'm not sure why it's happening now. I'm running the same 416 heads with the same valves/springs/cam/etc as before the tear down. I'm using Autolite 26 plugs, which should be the correct ones for these heads.

I also verified #1 TDC on the compression stroke using a compression tester. The distributor cap needed turned about a half inch to get the rotor to line up with my #1 plug wire, but it was probably off due to me messing with it earlier.

I haven't tried to start it again yet because I want to figure out why the valves are hitting the spark plugs first so I don't cause any serious damage to the engine.

92RS_Ttop

iTrader: (3)

Got the spark plug issue sorted out and replaced all the plugs. Still a lot of clacking and noise when the engine is running. Going to readjust the valves tonight or tomorow to see if that helps any. I put the timing light on it again, and I can see the mark now but it's almost at the 12 o'clock position on the balancer. I tried turning the distributor to bring the timing down to at least on the tab, if not to 0* on the tab, but the engine died when I got the mark to about the 1 o'clock position. The timing tab is at the 2 o'clock position, and I'm using the original timing cover and balancer that were on the engine, so I'm not sure why the timing is so far off. I have the vac advance disconnected for now, and the port plugged on the carb.

92RS_Ttop

iTrader: (3)

Just an update on the last post in case someone with similar problems finds this thread in a search.

The noises while the engine was running were coming from a bad alternator bearing. The rear bearing cover fell off at some point and most of the bearings were gone. It eventually seized completely one day while I was running the engine trying to pin down the cause of the noise. New alternator and belt fixed it.

The timing issue was my own fault. I failed to let the engine warm up enough before checking my timing. The manual choke was still closed and the RPMs were high enough to trigger the mechanical advance in the distributor. Once I let it warm up and the idle dropped,I was able to turn the dizzy enough to get the timing at 12* initial advance. Engine runs good now.