Hi All (especially those that have provided advice to date),Went up to the farm over the weekend armed with the necessary tools and equipment to replace the head gasket on the TEA20. First thing we did was run a compression test which registered well on cylinders 1, 2 and 4. Cylinder 3 didn't even register on the compression tester. We removed the rocker cover and found that one of the valves on cylinder #3 was stuck open. This exact same valve has been playing up on the tractor for over 30 years and I'd be interested to hear if anyone on the forum has had a similar problem and how they went about rectifying it. The short-term solution was a few light taps with a hammer to free up the valve and have it running smoothly again. After that, we removed a push-rod on #3 for inspection - BIG MISTAKE. The cam follower came up out of it's sleeve and turned sideways into a cavity in the block. It took about an hour to seat the cam follower back into its sleeve (with a piece of fencing wire) and I think it was more a fluke than anything else that it went back in. You blokes on the forum probably knew that might happen but it certainly surprised us. With the valve 'freed' and the cam follower back in its rightful position, we made the necessary adjustments to the rocker arms and put everything back together. To our great delight the engine is now running like a dream on all 4. We decided that there was no need to replace the head gasket given the smooth running of the engine and consistent compression on all cylinders. Water in the oil might be from the banjo seals in the sump that John UK eluded to so we'll wait and see about that. Hope I haven't bored you all with my rambling but we were all pretty pleased with the outcome. If anyone can tell me why a specific valve would play up like that for over 30 years, I'd appreciate it.
| 
