Bad Day

C

cpetku

Junior Member
Took the 31 roadster out for a parade and later a country drive. Everything worked great. Later I started her up to go on one more drive and half a mile from the house the throttle jammed and the engine made a bang then shut down. No compression on #2 and #1 seems low.

Hard to believe the engine blew in the time I was shifting gears with the throttle stuck.

Not looking forward to dropping the pan as I assume this is a $4K+ repair

--Craig
 
If you are able to turn the engine over to get a compression check it may be that you only blew a head gasket between 1&2. FelPro R3 head gaskets are very narrow beteen 1&2 and 3&4, and that is where they generally blow.

Tom Endy
 
Hard to believe an engine would grenade at wide open throttle in that short time. Always look on the bright side. Close to home, flying piston didn't take off somebody's head, etc. Best of luck to you in your time of need. Lots of help waiting on this site at your request.
 
Sorry to hear about your misfortune... hope it's nothing too serious...

As long as you didn't have a rod come through the block, you can have hope for repairing this engine....

Please keep us informed.

SC Frank
 
Having trouble finding a swivel to get the last few oil pan bolts out, but no signs of metal fragments in the oil yet. Just for fun I pulled the distributor cap and cranked the engine. No movement on the rotor. Maybe I'll get lucky and this is just a bad fiber gear and not a thrown rod I'll keep you guys informed on what I find in case I need anything.

Even if there are no bad rods, the pan needs to come off for painting. I just wish I could fix the rear leak (slinger) without pulling the crank.

Note my comment on compression was just an observation of air flow through the spark plug holes and not based upon a gauge.
 
Last edited:
Before you pull the pan, pull the side half of the timing cover (two bolts side, one bolt bottom), and see if the cam gear is turning when you turn the crank... might've eaten the cam gear...
 
Might have eaten the cam gear as mentioned or snapped the cam, either way those are cheaper than a total rebuild.
 
thats bad, if you will feel any better around 10 years ago i paid around 4000.00 for a complete rebuild, lots of $$$ 10 years ago, oil pump bushing to tight locked up builder did not care .water under the bridge now.
 
Cam gear is definitely shot. Not turning when I hand crank the engine and the side visible with the cover removed has a missing tooth as well.

I assume this is a non-interference motor. When the cam gear fails while the motor is running do they typically cause any other engine damage?



Also any hints on the front two/four pan bolts. It almost looks like I have to lift the motor to get them off. I still want to inspect the rods to make sure #2 isn't damaged but it may be that the valves are totally open on this cylinder. I assume cleaning the pan would be a good maintenance item since I got the car last year and it had been ignored (mechanically).
 
Yeah you got it, lifting the motor usually helps. I don't think they cause too much damage and I say that loosely because every instance could be different.
 
Front pan bolts are easy to remove if you turn the wheels to one stop or the other & use a straight 3/8" drive ext & ratchet.
 
Thanks for the tip on turning the steering. I had thought about disconnecting the tie rod to get the linkage out of the way.

Strange design, since the timing cover is part of the front mount I'll have to shim the bolts up before I can finish removing the pan and inspect for additional damage.

The camshaft gear is off and about half the teeth are missing (guess they're in the pan). It looks like the original as it has the Ford script emblem and patent date stamped into it. I guess after 81 years it's got a right to fail. Probably a heat related issue since we were slow in traffic and I know the water was boiling in the radiator (I heard it upon arriving home).


I'm feeling much better since I assume only one thing blew, and relatively close to home. It would have been a real issue having this happen on the way to the dairy where I took mom (81) out for an ice cream after the parade. Likewise, having the car die and block the parade route would have been quite upsetting as well. Guess someone was looking out for me today...
 
All flatheads by design must be non-interferance engines. Sure hope a rod didn't let go and mess up the cam, or worse. :confused: That's what I found on an engine I bought years ago. The oil pump came out of place and just about everything inside the engine was junk.:mad:

BTW, don't feel alone. I also had a bad day. I took my 1918 Evinrude to the lake for a nice day of boating. The last time I ran it was 1976 when I bought it. I got to the middle of the lake and had to stop the engine because I could see the water pump wasn't pumping. Rowed back to the dock and tapping and priming got the stuck check ball unstuck so it would pump water again. Then it was running great until I stopped it on the far side of the lake to pull weeds out of the prop. Lost spark and had to row back to the dock again. Loaded it up on my trailer and as I was driving up the ramp the rope on the hook broke and the boat launched out the back of the trailer onto the pavement. bent the gas tank and bent the skeg as it hit the pavement and the hit knocked it right off the transom. This was the first time out since I restored the engine back in 1978. Now I get to take the tank apart and restore it again.:mad:
 
Last edited:
It could have been worse....

Good opportunity to drop the pan, clean-out the sludge, check the bearings... etc.

Also, when replacing timing gear, it's best to replace the plunger and spring in the front timing cover: this keeps pressure against the cam-shaft. Frequently, the springs break from fatigue, and just collaspe in their bore, allowing the cam to "walk" back and forth, causing a pounding noise that sounds much like a bad rod-bearing: the noise is the cam-gear slamming forward into the timing cover.

Lost a Westinghouse-Micarta cam gear in my '28 due to this last summer; fibre gear finally separated from the metal hub.

When I replaced the gear and buttoned everything back up, and fired-up the engine, my "rod-knock" had mysteriously disappeared...
 
If the timing gear is stripped you will get the exact readings on compression that you have. The pistons are moving but the cam is not opening and closing the valves so, some are permanently open and some are closed. This would not allow the cylinder to fill with air properly. I would fix the gear first before removing the head but the pan needs to come off to clean out the stripped teeth. The two front bolts can be removed by turning the wheels to one side or the other. This will allow the drag link to move forward or rearward to get it out of the way enough to get to the bolts. I have never had to jack up the engine to remove these bolts and I have removed lots of pans.
 
You must log in or register to reply here.
Back
Top