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ohcruiser
10-19-2005, 09:17 PM
Iv'e got a '64 Cruiser that I just drove to Spokane and back. It ran fine all the way out and back (5300 miles), but the front seal disappeared on the way home. After I replaced the front seal when I tried to start it, it back fired and I lost ccmpression on 1,3, 2 and 5. I've taken the front cover off replaced the timing gear,(not stripped or broken) pulled the cam, (it looks OK), pulled the timing gear off of the crank (not cracked or stripped)and check both of the keys (straight as an arrow). To me the only thing left is a broken crankshaft. Anybody have any ideas before I pull the engine and take the crank out?

11SecAvanti
10-19-2005, 09:35 PM
On the backfire and lost of compression. Was that before or after you pulled the cam? Did you line up the marks on the cam gear to the crank gear? Is the distributor rotor in phase with the firing order. Your sequence of problems seem out of order. If the crankshaft is broke it will be a first for studedom.

Start and Stage Your Studebakers

Studecruiser64
10-19-2005, 09:42 PM
It backfired before I took anything but the front seal and cover apart.The rest came after I found that it didn't have correct compression

Roscomacaw
10-19-2005, 10:54 PM
Have you tried cranking the engine with the timing cover removed and observed what goes on there? Sure seems odd that you'd have compression on the other four cylinders and not the front ones! Since the cam has to work the valves in unison with the pistons and the cam's driven off the front of the crank......
I've known of two 289 Cranks that broke in two. But they just laid down and quit.[xx(]

Miscreant at large.

1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe
1957 President 2-dr
1955 President State
1951 Champion Biz cpe
1963 Daytona project FS

gordr
10-20-2005, 02:28 AM
Wow! That's a weird one.

I've seen two engines with a broken crank, a VW van and a Diesel Suburban. Both could run. I actually drove the van home about 20 miles with the broken crank. It had a real LOUD knock, like hammering on an anvil.

I didn't hear the busted 6.2 run, but the mechanic who first looked at said he started it, heard the knock, and shut it right down.

I doubt your Cruiser has a broken crank. If it had suffered a similar failure, it might still run, and should still have reasonable compression on all cylinders. Were the crank broken badly enough to stop any pistons from moving, the timing gears wouldn't turn, either.

Seems to me the obvious easy diagnostic check would be to pull the distributor cap and see if the rotor turns when you crank the engine. If it does turn, then the camshaft at least has to be turning, too. The valve timing might be messed up, but at least you have demonstrated continuity of drive from the flywheel, forward through the crank, through the gears to the camshaft, and back the length of the camshaft to the distributor. Doesn't absolutely preclude a broken crank, because they can break in the web so that one half drives the other.

If the distributor rotor does not turn, then either you have a broken roll pin holding the gear on the distributor shaft, or else the camshaft is not turning, since you said you had the cam out and it's intact. Next step in this case would be to pull the distributor, and check the gear visually. Should be easy enough to spot a busted roll pin. Take note of where the rotor pointed before removing the distributor, and if the gear and roll pin check out OK, replace it in the same position.

Next, I'd disconnect the line from the fuel pump to the carb, put a catch can under the end of the pipe, and have a helper crank the engine. If you get a squirt of fuel every other revolution of the engine, then at least the FRONT of the camshaft is turning. If you get no squirt of fuel after cranking for a few revolutions, then I'd go ahead and remove the timing cover, and then observe what happens when you crank.

You say you replaced the timing gear? Any chance you installed a 6 cylinder gear by mistake? I believe they are much the same size, but have the keyway located differently.

While you are at it, pop the valve covers off, and watch the rockers as you crank the engine. If they all move, then the cam and timing gears are doing their job. Look at the valves for the dead cylinders, and see if you don't have valves sticking open on them.

I'm kind of leaning toward the possibility that you got a tank of bad fuel, or maybe added some contaminated oil, and the valves are sticking in the guides (and sticking valves can sure cause a backfire). Contaminated oil could be what took out your front seal. Or maybe some lowlife sugared your gas tank.

If you do find sticking valves, I'd recommend that you drain both the crankcase and the fuel tank, saving maybe a quart from each to send to a lab, since possibly if the engine damage was caused by contaminated fuel or oil, it might be covered by insurance. I worked on a Camaro one time that had had its fuel tank sugared, and sugar was readily visible on the bottom of the tank, so once the tank is drained, try to get a look inside it, perhaps by way of the sending unit opening. If you do see sugar or other unwanted debris in there, remove the tank and have it steamed out.

Do post back and let us know what you find.

Gord Richmond, within Weasel range of the Alberta Badlands

Blue 15G
10-20-2005, 09:31 AM
Regarding the remark that if the crank is broken it will be the first for Studedom: I bought a used 259 several years ago which I saw advertised in my local paper. Seller said it needed rebuilt as it had a "slight knock".

Took it to my machine shop and they started to dismantle the engine at the top end. They said they couldn't believe how good everything looked.

Then they got to the bottom end and the crank came out in two pieces! [:0] "Slight Knock" indeed!!!

Studecruiser64
10-20-2005, 10:58 PM
Maybe I should start again. After I fixed the oil seal when I tried to start it it backfired. The only thing that had been taken apart at that time was the front cover and water pump housing.
When the car wouldn't start i removed the front cover again, checked the timing marks on the gears which were lined up. My second thought was one of the keys on the crank or cam had sheared. I pulled the cam gear off and the key looked OK. Iput a new aluminum timing gear on although the old one didn't look bad. The next thing I thought of was the cam had broken or wiped a couple of lobes. I took the valley cover off pulled the rocker arms off, and pulled all the push rods and and lifters. No damgage on any of the rockers, no bent push rods and no cupped lifters, and the cam looks perfect. I then pulled the crank timing gear off hoping the key had sheared there. It hadn't. I know the idea of a broken crank is kind of farfetched, but I don't have any more guesses as to what else this could be.

Dwain G.
10-21-2005, 12:10 AM
How did you determine those particular cylinders have lost compression? You had all the plugs out and used a compression gauge? With the plugs out and a good, bright pen-light in hand, look in each hole while the engine is cranked over by a helper or a remote starter button while you watch for piston movement. Verify that there is piston movement, then have a helper 'rock' the engine back and forth while you watch for any lost motion in the piston travel. That's probably the quickest way to check for a crankshaft problem.
If cylinders 1,3,5,and 2 have no compression because those pistons aren't moving, I'm curious why cylinder 4 isn't dead also. Could this engine have injested a large amount of raw fuel or water to cause a hydraulic bind?

Dwain G.

Studecruiser64
10-21-2005, 06:58 AM
I shouldn't have said no compression, they have betweem 40 and 70 pounds on the ones that are low. The rest of them run between 135 and 150. I ran a compession test on it before we went to Spokane and all of them were 160 to 165 after I adjusted the valves.
Dave

curt
10-21-2005, 08:10 AM
Two headgaskets blown?

Dwain G.
10-21-2005, 12:41 PM
I think your next step should be a 'wet' compression test, or better yet, a 'leakdown' test. The results may explain why the front seal started leaking so badly. If you took the oil fill cap off while the engine was running, was it 'huffin and puffin'? Did the engine overheat sometime during the trip home?

Dwain G.

Roscomacaw
10-21-2005, 02:16 PM
Well, 40 to 70 is alot different then no compression. No compression on the front cylinders while having compression on the rear cylinders would be hard to fathom as a result of crank failure when ALL the cylinders rely on the cam-crank gears doing their job up front.;)

Have you tried to start the car since that backfire[?]

Miscreant at large.

1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe
1957 President 2-dr
1955 President State
1951 Champion Biz cpe
1963 Daytona project FS

11SecAvanti
10-21-2005, 09:57 PM
I do not believe the crankshaft is broken. You are getting some compression on all cylinders. The starter cranking noise knock from a broken crankshaft would be very telling. I would think the motor would actually lock up. Assuming the crank is good and the cam is good and aligned to the dots then the cylinders are leaking compression either by the rings and or the valves or a blown headgasket. The original issue of lost oil by the seal indicates a bad seal, yes, but also excessive blow by in the crankcase from worn cylinders and /or rings and /or blown headgaskets. The orginal backfire you got on the attempt to start was probley an intake valve staying open or leaking when another local cylinder fired. You can get a backfire on a good engine when cold at times. May be time for a rebuild to cure the low cylinder compression. Perform a leak down on all cylinders to determine if it is rings, valves and or headgasket. Good luck. Nothing here that time and money can't solve.

Start and Stage Your Studebakers

Studecruiser64
10-22-2005, 12:58 AM
Thanks for all the suggestions. The front seal died of old age. There wasn't much left of it when I got the front cover off and it was about the consistancy of a burnt pancake. The valve timing is off somewhere,you could hear it when I tried to start it after it backfired. Before it backfired it sounded normal. I hope to get it the rest of the way torn down this weekend.I'll put a post on here about what I find. Thanks again for all the suggestions.
Dave