Hi everyone,
I have been doing some work getting the car running well, and after some difficulty with the carbs and discovering a missing exhaust gasket, I have got the spark plugs showing healthy combustion and fitted a new gasket so everything was running well and the car really driving nicely.
After getting back from a spirited drive I noticed a ticking at idle. I pulled the valve cover and checked camshaft timing, these were out and so set them correctly according to guidance posted here (as well as following the manuals).
After starting and idling again the ticking is still there, and the timing of the tick sounds like a camshaft or valve problem. While listening around the engine to identify where it was coming from I noticed that there is a leak where the exhaust manifold meets the block, which probably just needs to be tightened some more.
BUT! At the point where it is leaking I noticed a few drops of coolant! Where this could be coming from I can only imagine its leaking into the cylinder but theres no white smoke from the exhaust. It appears to be below the exhaust port for the number 2 cylinder.
Any guidance for what I should do before I pull the head off and replace the head gasket would be much appreciated.
Ticking and coolant leak at exhaust gasket
Re: Ticking and coolant leak at exhaust gasket
A follow up after tinkering today.
I decided that a compression test might help with the diagnosis, so got the car up to temperature and upon removing the spark plug for cylinder 1 I saw a little bit of coolant on top of the piston.
So I think I have my answer, the cylinder head needs to come off. The ticking will be revisited once it is all back together again.
I decided that a compression test might help with the diagnosis, so got the car up to temperature and upon removing the spark plug for cylinder 1 I saw a little bit of coolant on top of the piston.
So I think I have my answer, the cylinder head needs to come off. The ticking will be revisited once it is all back together again.
Re: Ticking and coolant leak at exhaust gasket
Most likely yes the head has to come off.
You may try re-torquing the head as it is. Probably a waste of time.
Check that the edge of the crown of the pistons is level with or just under the top of the block at tdc. If not, correct with thickness of foot gasket.
The standard head gasket is 1.2mm. Put clay on top of the piston. Put on head gasket and head with only 2 bolts. Turn engine. Check that distance between piston and head is 1.2mm.
If the diameter of the combustion chamber in the head is less than the diameter of the dome on the piston the distance may be less there. As a result air cannot escape at the end of the compression cycle which results in detonation. A frequent cause of ticking.
You may try re-torquing the head as it is. Probably a waste of time.
Check that the edge of the crown of the pistons is level with or just under the top of the block at tdc. If not, correct with thickness of foot gasket.
The standard head gasket is 1.2mm. Put clay on top of the piston. Put on head gasket and head with only 2 bolts. Turn engine. Check that distance between piston and head is 1.2mm.
If the diameter of the combustion chamber in the head is less than the diameter of the dome on the piston the distance may be less there. As a result air cannot escape at the end of the compression cycle which results in detonation. A frequent cause of ticking.
Re: Ticking and coolant leak at exhaust gasket
Hi Huib,
Thanks for the recommendation, I have taken the head off and now busy cleaning and inspecting everything, so I'll take a look at the clearance you mention.
When removing the head, and then the camshafts on the bench, I noticed a rocker arm was contacting the valve pushrod even with the adjusting screw removed. I found this old thread where the same issue was raised but no discussion on how to solve it:
viewtopic.php?t=4900
Thanks for the recommendation, I have taken the head off and now busy cleaning and inspecting everything, so I'll take a look at the clearance you mention.
When removing the head, and then the camshafts on the bench, I noticed a rocker arm was contacting the valve pushrod even with the adjusting screw removed. I found this old thread where the same issue was raised but no discussion on how to solve it:
viewtopic.php?t=4900