Rover Sports Register Forum

iM Back helping my friend with his 1947 12HP .Some months ago he asked me for help with his engine I found there was no compression on a couple of cylinders and two push rods were bent .I removed the head and took it home for repair ,I found two valves has just touched the pistons causing slight damage to them.I also found,a few of the valves were tight in their guides so after several hours work I brought the head back to looking great I even left petrol in the chambers overnight and perfect .My friend reassembled the engine ,but it sounded awful .So today I went back armed with a clock .I measured the number 1 exhaust valve as compared the the correct mark on the flywheel EP1 and it was within 0.04mm (top of lift ) I then checked the ignition timing and again with the correct mark on the flywheel FA4 .So I am now at a loss I am having treatment for cancer,so the less worry I have the better,but what can you do if someone asks for help .My friend has fitted a new tappet shaft and I set it correctly when I rebuilt the head .Someone has told him,that the cam shaft can cause problem,but I don`t see how the problem could have happened He has mentioned ,that after having a new clutch plate fitted last year the car seemed under powered ,but he has averaged 39 miles a year for the past 12 years !!!!! .The car is in stunning condition and I think its his pleasure to go into his garage and polish it .Any help would be more than welcome Ive just bought a classic car this week,so I am going to have ongoing work to do .If its a case of the camshaft needing replacing how much of a job is it .I noticed that the crank pulley is close the the cross member so the engine needs to be lifted at least Len

Please measure the compression. Measure the vacuum when idle in normal operating temperature. Is the exhaust OK? What head gasket have you used?

Morning the compression on number 1 cyl is zero The owner has a metal head gasket which he had bought already Someone suggested that the cam may be the problem,but I can`t see how a faulty or rather worn cam ,could move the valve so it contacted the piston. If the cam needs to be replaced can it be done it situe .Its not a job I really want to get involved in it ,the owner lives a few miles away ,so its not like working on your own car ,where you can just pop into the garage for a short while. My health isnt as good as it could be and I have a classic car which I bought to slowly restore .I wouldnt mind ,but the fact I rebuilt the head which looked like a new one,then to go through the trouble again and not knowing the cause is frustrating Len

Take the car to a garage with good reputation and experienced mechanic. You are not going to get out of that by your own.

Thanks Luli I think it has to come to this point I have my own car which I bought last week to give me something to do I also am having treatment for cancer,so I don`t want the worry of someone else`s problems and finally I have a house which always needs work on it

Ive persuaded the owner to take the car ,back to the garage he used to use At least they have the equipement and tools for the job.However,it will be very interesting to know the cause Len

Hi Len,

A number of us have followed this issue with interest so do, please, update us once the garage resolves the problem.

Did you determine why No1 had no compression and was this one that had bent valves before? Was just thinking that, as the car stands for long periods, the cam followers may be sticking. If this was the case you should be able to see that the valves are not fully closing. I’ve not had this problem on a running engine but a couple of the followers in my Tourer were really stuck when I stripped it down to rebuild and I had a real job removing them. I assume the six is much the same as the four in this respect.
The piston coming up would knock them shut I guess, but probably do a bit of damage like bending the valve and the push rod. All depends how stuck it was in it’s guide. Just an idea but lack of compression can only be a valve, gasket or piston ring. To have zero compression sounds most like a valve and the follower is the only variable I can think of that might keep one open.

Look forward to hearing from you and good luck with your new project car. Perhaps your friend would like to join the RSR and update us himself?

Tony.