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turning over an engine sitting for years ?

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beaulieu

beaulieu

Jedi Warrior
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Hi

the 120s motor has not been running in years , Ok decades

I was planning on pulling the plugs , dumping marvel mystery oil down the spark plug holes to loosen it up , then letting it sit a few days , and repeat....

What size socket do I need to turn the crank at the front pulley ?

If any of the valves are stuck open will the piston hit it when it comes up ?

I only want to turn it over with a socket and breaker bar until I know it turns over OK....

any other ideas ?

thanks

Beaulieu
 
I don't remember what size socket fits on the crank.

It would probably be a good idea to get some oil down the distributor shaft, & lube the distributor cam.

You need a shop manual. I don't see one on CD listed at the Heritage Motor Center, but paper factory shop manuals are available:
https://www.amazon.com/Jaguar-Service-Manual-Mk-VII-MkVIII/dp/0837605687/

Haynes & some others had shop manuals, but you really should start with the factory manual. It's the first thing you should buy, & consider it a part of the car's purchase price.

I think the XK 120 head is a non-interference design, so the pistons shouldn't collide with the valves. I'd take the valve covers off & make sure nothing's amiss in there before turning the engine, though.

Fender skirts were fitted only to the rear, & only if disc wheels were fitted (not wires).

I had the hardback edition of this book, _The Jaguar XK_ by Paul Skilleter, there's a paperback version at Amazon:
https://www.amazon.com/Jaguar-XK-Paul-Skilleter/dp/1899870571/

It was a big help with my near-basket-case XK-140. It's a really good overview of the XK series, history, development, interchangeability between cars (much is interchangeable between the 120 & 140), lots of pictures to see how things should go back togetherin the cockpit, etc.

The XK's had honeycomb-type radiators which don't really age well. I'd flush the cooling system forwards then backwards several times, then be unsurprised if it doesn't cool well enough. If you do get by with the original radiator, fabrication & installation of a fan shroud makes a BIG difference in cooling.
 
Hi....

thanks

Anyone know the socket size so I can pick on up at the swap meet this weekend ?

its got wire wheels so no skirts,,,,,and I really liked that shirt look, ohh well.....

I am getting a mouse eaten factory repair book with it so that will help,

:It would probably be a good idea to get some oil down the distributor shaft, & lube the distributor cam."
I never thought of that ....thanks

Right now I am just planning on getting it to turn over, then I can worry about the cooling and fuel.

Thanks for all the advise

Beaulieu
 
1 and 5/16ths inches is what I need to turn the crank bolt in my 3.8 XK engine.

edited for additional input:

the trouble is - if the radiator is in place, there might not be enough clearance to insert the large socket and wrench between. Knowing how tight these cars are, I bet you'll need to remove the radiator, and that means releasing the Belt tension at the Generator adjuster so that the fan can rotate freely, and if there's a Shroud over the radiator, that needs to be unbolted first, and the hoses and who knows what else is there.

An easier procedure in order to move the car is to unbolt one side of the drive shaft, (4 nuts and bolts), keeping the driveshaft away from the floor with a clothes hanger.

then pull the car onto the trailer with a winch. I really don't understand why you want to turn the engine, it's probably seized anyway. Are you hoping it will Start?
 
120 *should* be the same. Lots of Marvel down th' pluholes, be patient for a day or three, turn the thing only in the direction of running rotation (clockwise facing the front of the engine), cam covers off... watch for sticking cam "buckets". That would be another place I'd slop generously with Marvel oil, BTW.

This is quite exciting, actually. /bcforum/images/%%GRAEMLIN_URL%%/laugh.gif
 
> ... watch for sticking cam "buckets". That would be another place I'd slop generously with Marvel oil, BTW.

Also lube the cam bearings too. The MM oil is thin enough to get inside the bearings if you apply it to the edge of the bearings.

I don't remember if the XK120 engine's oil pump is driven by the distrutor shaft. If it is, you can remove the distributor and operate the pump with an electric drill and a home-made adapter. That would oil the rod and main bearings too. They are sure to be dry after sitting that long.

Don
 
Unfortunately the oil pump is gear driven from a helical gear at the front of the crank. Pre-oiling it that way is off the table. /bcforum/images/%%GRAEMLIN_URL%%/frown.gif
 
Thinking on this, if it can be turned through 360* by hand after all the soaking, inspecting, etc. it ~may~ be worthwhile thinking over spinning it on the starter to see if pressure comes up, BUT: the only really certain way to insure it'll be right would be to pull the beast out and go right through it. Dunno which would be more costly: doing it now or doing it after it spins a bearing... I don't think I'd risk an attempt to run it after its sat as long as that has. Think cubic dollars here.
 
Hi

thanks for all your GREAT advise,
I know nothing about these motors....

If I cannot get to the front pulley is there any way to get to the flywheel and turn it over from that end ?

First thing to do is see if it turns....
then I can get deeper into it,

Hey maybe it even runs /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

Beaulieu
 
have you already bought the car? If so, you can easily damage the flywheel trying to turn an engine that has not moved in decades. I think the whole idea is pointless, it won't prove anything if you can turn the engine. Do you know a lot about engines?

If you haven't bought the car yet, will the owner let you do all that before you pay for the car? If you don't know, I'll take a guess: I don't think he's going to let you tear the car apart just to see if the engine will turn. He wants you to pay and then take the car far away where he won't see it again!

Overall, I think you should have bid on the eBay XK-150.
A running car that would have taken you home after picking it up. Based on your questions, you sound like that you're not familiar with these cars, or any old car that has sat for 3 decades. You are looking at a complete engine rebuild whether you can turn it or not. It is not going to come back from the dead with Mystery Oil and new spark plugs. Sorry to break your bubble.
 
Hi

I have many old cars, just not Jags ,
and I have started motors that have sat for 20-30 years ,

I do not know anything about Jags except what I read here and elsewhere on the internet,

I have bought the car , so any work I am going to do on it is when I own it not the old owners ,

As far as the Ebay car , well I never saw it till it was already sold ,

Beaulieu
 
It's his now. Other than just determining there is nothing totally seized, turning it by hand is an encouragement. Trying to START it would be a mistake, IMO. For the cost of the bits which can be trashed in seconds of run-time it makes little sense to chance it. Jags are solid, but the time this sat inert would have me just resigned to disassemble it to component-level and go from there. Resurrecting it from what's left as opposed to trying to source out replacement blocks/cranks/heads etc. because of some unknown internal problem trashing BIG, expensive parts is a mistake. A time consuming, costly one.
 
No matter what I do , I still need to get it to turn over,
even if I take it apart later to rebuild it.

I am just trying to do the least harm I can ,
i would be asking pretty much the same questions if it was out of the car and froze up....

Beaulieu
 
Yup. Seeing if you have components or a solid LUMP is the question. Soak it well and see.
 
ok, Beaulieu, now I understand where you're coming from. Congrats on buying the car. How much? (if ok to ask) A picture would be nice. Remember to document the restoration with pictures or video, it adds value to the car.
I bought my cheap crank-bolt socket at the auto parts store, $4.19 plus the dammed sales tax. I figure it will be good for a few removals and torquings, and if it breaks, so be it. This one was Made In Timboktu I guess. so far so good.
 
I have no interest in "restoring" it

I will clean it up , buff out the original paint , polish the chrome etc.

If there was a presentation class this would make a great car to show, as it seems to be very original.

If I can get it to turn over thats a plus,
first I need to get it to roll, hopefully the brakes are not frozen , and with luck some of the tires will air up,
I think its still got the original spare,

I must say that this is not my dream car , It just showed up, I would rather have a 356 speedster but have not found one so this will have to keep me happy until I find a Speedster....
 
Now you're just bein' a TEASE, Ex. /bcforum/images/%%GRAEMLIN_URL%%/smirk.gif
 
Exotexs said:
1 and 5/16ths inches is what I need to turn the crank bolt in my 3.8 XK engine.
Click to expand...

I am "almost" certain that the reason I bought the 1 and 5/16ths inch socket I have is because I needed it for my own XK 120 engine, when I had a 120. It is the same bolt as on any XK engine I think. I know my 4.2 Litre EType is the same also. So I think you have your answer.
 
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