Head gasket? Or new engine?

[beagle]

Hello again, What should I make of this? My R4 has white smoke coming out of the exhaust.

I first thought it would go away as the car has been stored outside for about a year without being started, and the smoke was being caused by moisture in the exhaust and the engine. But I've had the car running for about an hour and it's still there! The strange thing is it doesn't over heat and only uses a tiny amount of water (expansion bottle dropped 7mm from max level after 30 min of use).

I ran the car for half an hour yesterday afternoon and left it overnight. In the morning I undid the expansion bottle cap and there was no hiss. However there was a milky sludge on the oil filler cap. Oil on the dipstick is ok though and there is no oil in the coolant.

See the pics of the offending article: http://s735.photobucket.com/albums/ww351/XKss21/Head Gasket/

I took the plugs out and did a compression test all cylinders quickly got to 150 psi (10.34 bar). Plugs were a bit sooty but not oily.

So is this defiantly the head gasket/ cracked head or could it be caused by something else??

The engine has done 85 thousand miles so I'm not sure if it's worth fixing the head gasket (It does have unleaded valve seats though.). My Haynes manual says I need some special socket to remove the head and that the wetliners can be troublesome. Any one with a spare engine for sale??

Although the car looks scrappy, the chassis is in really good order so it's certainly worth spending money on. I just want to get this car finally finished!

Any advice would be greatly appreciated. I've learnt a lot from this forum

Tim

 

[pepper]

These engine have over head valves so the top of the engine runs cooler than more modern OHC engines so they do tend to build up sludge in the rocker covers quicker than our more modern equivalents. if the Compressions are all good and there is no oil in the water or water in the oil then don't worry about it. Just get on with driving it.

 

[beagle]

Thanks pepper, but what about the smoke? It is actually worse in real life than the photos. I can't imagine it would pass an MOT like that. Could it be something to do with the emissions system?

p.s Very sad about Sheldon Brown, I only got into classic bikes last year. Seems like a wealth of information. Great his website is still running.

 

[malcolm]

The oil cap does look very sludgy, so it could well be the head gasket. They can sludge up a bit with lack of use, but not normally that much.

Changing the head gasket isn't too difficult - you just need to ensure you don't disturb the liners. Trick is to remove all the bolts gradually, screw one back in finger tight in a corner to stop the head from listing. then knock the head sideways.

You'd need to be careful removing the old gasket. I used a "strip and clean disc" for my last one which worked OK - you can be very gentle with them. Then bolt eveything back up like it says in the book of Haynes. Careful not to turn the engine over when the head is off.

Much easier and quicker than swapping an engine.

Oh, is the coolant system pressurising properly? Does it hiss when you remove the cap a little when warm? That's worth checking as it can cause overheating.

 

[angel]

The sludge you see on the oil cap is fairly normal. It could well have been caused by condensation in the oil. By running the engine one hour, and then another half an hour, don't expect the oil to be at its normal temperature. You should make a lengthy road trip (and with this weather, you should have a thermostat fitted).
The "white smoke" is 100% normal. Exhaust gases contain a lot of water vapour. No matter how hot the engine gets, the exhaust tailpipe will still be cold now in the winter, giving them a place to condensate.

I bet your engine is fine, but make a final test. first make sure you have no leaks and the cooling circuit is properly bled (the best way is to fill it through the expansion bottle, with the latter removed from the inner wing and held as high as possible). Pay particular attention to the heater, on the GTL it is effectively located higher than the radiator. When you are sure the circuit has no air pockets, bring the engine to normal operating temperature, check again that the cooling system is bled, open the expansion bottle cap and check that the coolant there is not bubbling. You can check this through the radiator fill plug too.
In any cases there should be no bubbles in the coolant.

 

[malcolm]

You should make a lengthy road trip (and with this weather, you should have a thermostat fitted).

That is good advice actually. For the UK MOT test the white smoke is unlikely to matter, especially if you insist the car has been sitting for a bit and probably has water in the silencer. Worth getting the car through an MOT and driving it a bit to confirm if there are any problems before getting involved in extra work.

 

[Andy McGhee]

Hi Tim
Judging from the photo, I'd say it's quite likely that there's air in the cooling system - the pipe that comes out of the bulkhead should have a proper bleed screw in it, rather than the present arrangement (!!).

 

[beagle]

Thanks for all the info guys, really helpful. The cooling system seems to be working ok, it does not bubble and the top hose gets hot. After a while the cooling fan comes on and goes off after a little while. It hisses when opened while still hot.

I know the socket set extension clamped to the bleed hose looks a bit Mad Max but I can see no signs of a leak when the expansion bottle is held high. Also should I be stuck for a 1/4 inch drive socket extension out on the road I'll be happy :smile:. Is fitting a new bleed pipe tricky? I wonder if the part is still aviaible?

I'll take it for a good drive around the farm when I get the clutch unstuck and I'll see what it's like then. It's got to be ready for the Kent run! Any tips on getting it released??

 

[malcolm]

I remember the question about unseizing clutches. If the brakes work start it in gear, drive it around and use the brakes to free the clutch while you play with the throttle.

If it's more stuck than that there's a handy access hole that we normally use for setting the timing. With the engine off and someone pressing the clutch pedal a blunt knife down there can be effective.

 

[beagle]

Hephaistos said "let there be a clutch!"

Clutch has unjammed came away quite easily. I held down the pedal using a wedged broom stick and crawled underneath to find the inspection hole. I lightly tapped a knife from the best cutlery set and the plate popped off!

A quick spin up the drive and she's fine! Actually smoking less now. Words and smiley face symbols can't decribe the joy of driving Savanne again- it's the sort of thing people write songs about and paint nice pictures. Anyone musical??

 

[pepper]

I know the feeling, I've finally got my 4 running again tonight!