TC 74 Head Gasket replacement

[jrnicl5]

Just finished with the Stromberg carb rebuild and the engine was running fine until I saw a lot white smoke coming from the exhaust.

I opened the valve cover and saw coolant close to the valves. I ended draining the oil and in deed say coolant coming first and then oil.

This is a new adventure with the head gasket replacement.

Any advice would be welcome.

Should I remove the engine/transmission or I can do the job with the engine still on the car?

[BDA]

I don't have a TC so I can't be very specific about it. You can get Cometic head gaskets from the usual suspects (Dave Bean, r.d. enterprises, etc.). You should be able to change the gasket with the engine in the car. People have changed the water pump with the engine in the car so there's no reason it can't be done in the car. Here's the workshop manual online (http://lotus-europa.com/manuals/tcwork/e/tce.pdf). In fact, you should book mark the page it comes from (http://lotus-europa.com/manuals) as their is a LOT of good information there.

[jbcollier]

It's fairly straight forward to change the head gasket in the car.  Might need a little help to lift it off.  Make sure you bring the engine to TDC on #1.  Check your cam marks so you can get them exactly the same when you hook the cams back up.  Always, always, turn it over by hand two full revolutions and check your marks again.

Virtually every time, the jackshaft which drives the distributer will get out of sync.  Note where the ignition rotor points at TDC #1 and pull the distributer to set it correctly.  You'll have to double check your ignition timing as well.

Read, read, read on how to properly seal everything up.  Oil leaks are VERY common unless you are meticulous in your prep and assembly.

However, first, are you sure it's the head gasket that is leaking?  Hate to do all that work and still have the same problem.

[jrnicl5]

Thanks for the response, resources and advice.

When the engine was running, a lot of white smoke from the exhaust. Also, I noticed coolant in the valve cover area and when I drained the oil, coolant came first then the oil.

[EuropaTC]

Water in the oil does sound like the head gasket's leaking, but before you rip it apart I think it would be worthwhile to do a compression test and see exactly what you're dealing with.

If you're going to the trouble of replacing the head gasket then I would take off the drive belt for the water pump and check for for play in in the bearing.  It would be very annoying to strip the engine, replace the head gasket, re-time everything and then have to do it all over again 6 or 12 months down the line. (you need to remove the head to replace the water pump).

There's plenty of reference already for the task, but for my money the book by Miles Wilkins, "The Lotus Twin Cam Engine" is the definitive guide on the engine.

Brian

[4129R]

If the bolts are not rusty and easy to undo, it takes about 2 hours to get the gearbox off, and another hour to get the engine out if you have an engine hoist, say 4 hours tops.

The thought of getting the timing chain back on with the engine in situ is not a good one.

Once the engine is out, it is a doddle to change the head gasket.

[buzzer]

If you have the facilities I would take the engine out personally too. you'll no doubt find loads of other jobs you want to do on it too!

[BDA]

Water in the oil does sound like the head gasket's leaking, but before you rip it apart I think it would be worthwhile to do a compression test and see exactly what you're dealing with.

If you're going to the trouble of replacing the head gasket then I would take off the drive belt for the water pump and check for for play in in the bearing.  It would be very annoying to strip the engine, replace the head gasket, re-time everything and then have to do it all over again 6 or 12 months down the line. (you need to remove the head to replace the water pump).

There's plenty of reference already for the task, but for my money the book by Miles Wilkins, "The Lotus Twin Cam Engine" is the definitive guide on the engine.

Brian

A lot of great advice here! I would only suggest that a leak down test would be more appropriate than a compression test for this purpose. Besides helping you determine the effectiveness of your head gasket, you can also learn if any of your valves are leaking and which ones (and more). With your head off, it would be a good time to address them.

They are pretty easy make (http://www.lotuseuropa.org/LotusForum/index.php?topic=3696.0) or they can usually be purchased at discount tool suppliers.

[Dilkris]

The thought of getting the timing chain back on with the engine in situ is not a good one.
Once the engine is out, it is a doddle to change the head gasket.

  100%
People (many) on this Forum have done this work with the engine in situ but personally.... I wouldn't try it. It is fiddly enough with the engine out and if you are going to change the water pump also, most certainly do it with the engine out. For the cost of the water pump internals it would be unwise not to change the pump once the engine is out and the head off. Trust me - bite the bullet - take it out.       

[jbcollier]

I agree with all the suggestions to remove the engine but, it's a slippery slope.  The poster has been trying to get it running so he can try it out.  If you pull the engine, it's dollars to donuts that he will end up doing a complete engine overhaul.  As we have all seen before, the "project-stall-factor" increases dramatically if the engine comes out.  Heck most of us bought projects where engines were out or at least headless.  So he pulls the engine and finds it needs an overhaul.  He hasn't even driven the money pit yet so he hasn't fallen in love with it like we have.  And, it's not hard for a TC engine overhaul to hit eye-watering levels in very short order.

So, even though it is not what I would do, he should probably just replace the head gasket and get some driving time in.  After he's hooked, then the floodgates can open.  Maybe he won't like it (horrors to Betsy)!  Then he has a running project to sell which will fetch a lot more than the usual partially disassembled hulk.

[Dilkris]

Out of interest jrnicl5 - Earth is a big place - which part are you on?
If you're running "Strombergs" I assume you are not in the UK   

[jrnicl5]

I'm In Austin Tx, US!

Just a little background for those who are not aware. I bought the car on January 2021 from an owner who had it sitting for 40years. last time on the road was 1980. The car has only 12k miles. It's beautiful from the outside . The inside needs  the wood dashboard replaced, the driver side seat rail is rusted . I already replaced the rubber hoses for fuel and coolant, the fuel tank, expansion coolant tank , replaced the exhaust, muffler, spark plugs, and rebuilt the Stromberg carbs. I do have the clutch cable and the accelerator cable to replace too.

Now I am dealing with the head gasket. Jbcollier, you totally felt my position. And yes, I would like to at least drive it as a first step.

I have attached a few pictures of the car taken the day it was to be shipped to me.

[4129R]

If the car has only done 12,000 miles, I cannot see how the head gasket should have failed unless it has overheated very badly.

Are you sure it is not water from condensation with the engine sitting doing FA for 40 years?

I think you should check the compressions before you do anything mechanical.

[jrnicl5]

I did an oil and coolant change prior starting the engine

[SilverBeast]

I wish the bodywork and shutlines looked as good on my car as they do on yours!