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Triumph TR3 - Siezed Engine

Howard Petri

Let's try this again.
I just bought a 1959 TR3A a week ago which has been sitting for at leas 10 years. It's in pretty good shape externally ie no rust. But it needs a top and side curtains and such, hydraulics overhaul etc. It hasn't run in all of those years of course and when I got it home I found I had a siezed engine. I'm not really surprised but I was hoping to drive this car after fixing a few things and not have to restore it immediately. I am already up to my neck in a 1932 Packard restoration. Any suggestions for getting this engine turning? I am trying the standard stuff, Marvel Mystery oil in the cylinders, rock the car gently in gear, try turning it with the crank. And from my Model A and tractor restorer friend, hang a weight on the crank so there is always some force trying to move the crank. Any help would be appreciated.
Howard Petri

May-be it's seized. Try turning the engine counter clockwise to see if it moves. If it does, somthing may be broken inside and wedging it.

Maybe a con-rod is broken or bent. Or worse. Pull the oil pan and check.

Some Tool Rental Stores rent a video viewer to check all the down in sewers or sewer pipes. If you can get one small enough, put it down the spark plug holes and check.

Don Elliott, Original Owner, 1958 TR3A
Don Elliott

Thanks for the help Don. Since I can rock the car back and forth in gear I can apply force in both directions of crankshaft rotation. It doesn't want to move in either direction. I have been able to actuate the clutch so I know it is not destroyed. I suspect the engine is truly seized, most likely a cylinder. It's been suggested that I float the crank by draining the oil and completely filling the oil pan full of Marvel Mystery Oil. I am interested in dropping the pan and taking a look as well as pulling the head so I can perhaps tap directly on the cylinders and maybe apply some heat and more Marvel. I think patience is a virtue here.
Howard Petri

Sound like you can get away with a quick and easy fix. At least till to look more closely, maybe with the pan off.

Don Elliott

Hi howard:
TRs have removable cylinder liners and your problem is probably siezed pistons.I would strongly suggest that you do not tap aluminum pistons as they are not conducive to tapping.They tend to break before loosening.The best thing to do in my opinion is to drop the pan disconnect,the rods,remove the head and take out the cyl liners complete with pistons then you can soak them in penitratig oil,heat the sleeves and freeze the pistons or any thing else you would like to try(except beating the pistons).

If the engine is not mechanicaly siezed just rust.

Marvel etc. is way too expensive for a soak. You will need at least a week of soaking so your patience theory is correct.

Most of this comes from tractors and other farm machinery. They tend to rust up due to the upright exhaust and some are only used seasonal. Basic oops.

Fill the engine. We only used diesel fuel but some suggest mixtures of gear oil and Marvel or kerosene same as deisel but better refined for smell and other types of penetrants. Personally I grew up with diesel and I don't think there is a better rust penetrant made. Yep it stinks so a different mix may be better for you. Your looking at a few gallons?

And I do mean fill the engine to the top of the dip stick tube. What you want to do is soak and soften all rust so that when it does come loose you minimise the cylinder wall and ring damage because all the areas are soft.

Now find a suitable screw in replacement for your plugs or just knock the ceramics off old ones and drill out about 3/8" or whatever tube is handy. Take some brake line and make tubes fitted IE hammered in to the holes in the sparkplug sticking up add some clear fuel line and run each to a jug or jugs of some sort. Fill with your mix of choice. Clear line keeps you aware of whats empty.

You want the whole of all cylinders wet soaked for a good week. Top area is most important rusts worse. And the rings gap will allow the mix to flow down so just squirting gets you nowhere.

With frequent back and forth bumps unless its a broken ring whatever it should come loose.

When it does turn engine clockwise by the damper bolt keeping the fluid on it at least 20 turns at arm speed. Don't use the starter or you will have fluid all over and even at arm watch your tanks..:)

Buy some cheap oil and get her started run for 2 minutes. Change oil run for 10 change oil again to your regular. Change that in about 2 hours of running.

Bill Brayford

Well I have a lot of "variations on the theme" here to give a try. I thank everyone for their ideas. I guess I'd better give up on squirting oil down the cylinders and proceed to the flooding stage. It looks like this will take some time. I'd better be patient and not try and force anything either. I'll let everybody know if and when I succeed.
Howard Petri

Well I have never been able to get the engine freed up. I was able to locate another engine and I am in the process of installing it now. Today I managed to get the old engine and trans out of the car.
The new engine is out of a TR4 and while the engine itself is the same as a TR3 engine I just noticed that the front engine mount is different. Which means that I will have to swap them which necessitates pulling the timing gears. Anybody know of any other problems I might have in swapping these engines?
I'll keep the old engine and repair and reinstall it someday in the interest of originality.

Howard Petri

Don't forget to use the fan hub extension from the tr3. The one on the tr4 is slightly longer and could damage the radiator.
Mike Parkhill

One of your pistons probably has a lot of stuff (like minerals from water, dirt, and rust between it and the cylinder wall. I tried lots of force on mine, no luck. I even pounded on the top of the piston with a 4X4 and a sledge while a friend leaned hard on a breaker bar w/extension on the crank bolt. Luckily that didn't break, and neither did the piston by the way. But the pan came off, the sleeve and piston and rod came out thru the top, and to get the rod back, I had to take t to the shop with a press. You should have heard it bang every time the piston moved a mm. It got better each time, and finally came out. Now I could remove the piston from the rod. I might have been able to install oversize pistons and bored the sleeves at the motorcycle shop, but opted for a slightly used 86mm set, honed a little, and new rings with a step on the top one. The block never came out of the car.

You will have to change the plate to the later one. Don't know about the differences in fan extensions, etc.

Since the engine's out, why not rebuild the original? I recommend checking your crank end float (thrust)and rod bearings in any case, they're both so easy to change. And rings of course. You'll be more secure knowing a little bit about what's in there. RTM too.

This thread was discussed between 19/02/2004 and 22/03/2004

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