Greenside Spitfire Posted December 31, 2020 Share Posted December 31, 2020 Bought my Spitfire in November, it would only run on full choke. Took rocker cover off to find broken No 2 rocker and bent No 7 push rod. Replaced these and fitted new cylinder head gasket. Started fine but with steam from the exhaust. After leaving for two days would not start easily. Took rocker cover off again to find No 2 and No 3 push rods bent, and No 7 rocker push rods jumped out of location. Except for steam which I suspect is the head itself. Any ideas why rods should bend. Quote Link to comment Share on other sites More sharing options...
glang Posted December 31, 2020 Share Posted December 31, 2020 could it be that youve got valves stuck closed - something which can happen if the engine hasnt been run for a long time? Then when youve started it something had to give which will be either a bent pushrod or broken rocker.... Quote Link to comment Share on other sites More sharing options...
drofgum Posted January 1, 2021 Share Posted January 1, 2021 Colin, I'm mostly with glang on this. You should look at number 7 valve to check if it is now stuck part way open. If it is, that explains the pushrod jumping out of position. Even a slow returning valve can cause that. You might also take a glance at the inside of the rocker cover to look for marks where the valve adjuster screws have hit it. This is unusual, but does happen occasionally with skimmed cylinder heads and alloy covers. But do make sure all valves can operate as they should. Best of luck, Paul Quote Link to comment Share on other sites More sharing options...
thescrapman Posted January 2, 2021 Share Posted January 2, 2021 That many bent rods suggests to me the engine may have been skimmed, and the valve springs are going coil bound. have you checked the springs whe the cam is at max lift? Quote Link to comment Share on other sites More sharing options...
Greenside Spitfire Posted January 9, 2021 Author Share Posted January 9, 2021 Gentlemen, thank you all for your replies. I believe that I have the answer to my problems. When I bought my car in November it had been standing for 25 years, yes 25 years. I fitted a new cylinder head gasket and numerous other items plugs leads etc. I believe that the rods bent because the old petrol had somehow burnt gunge onto the inlet valve stems. OK when the engine was running but when left to cool solidified. Then when starting engine again held the valves open long enough for the rods to move away from their rocker location, then when coming back up collided and bent. I was badly advised to leave the old fuel as it was an "old wives tale" to remove it. I have changed it now. Rebuilding tomorrow, new gasket valve seats machined, valve sealing faces machined and lapped, new petrol, new oil new filter and hope in my heart. Quote Link to comment Share on other sites More sharing options...
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