QuestionQUESTION: I've been making some nice progres on bringing my 1979 mgb back to life after years in the garage. I'm having a problem with my valves sticking, the larger ones (Intake???) I had the head off cleaned them up and "lagged" them. However, after running the car briefly, it again wouldn't start. I pulled the valve cover off and again the same 4 valves were stuck in the down position, fortunately, no rod damage. I've been reading a little online about "oil seals". Am I heading in the right direction? Any suggestions? Oh, the valves have bronze guides, if that matters. Thanks.
ANSWER: Hi Ernie. If all 4 inlet valves are sticking, then either the guides are too tight, or they are gummed up. You don't need extra oil seals, but you should always replace the tiny rubber O rings that act as oil seals. I would take the head off again, remove the valves, and check that the guides are clean. You can pull a strip of rag soaked with gasoline through the guide to clear it. My guess is you will end up with a very dirty rag. Also, clean the stems of the valves with a hand-held wire brush and wipe them with a gasoline-soaked rag. Lubricate the stems with thin engine oil, then test that the valves slide easily through the guides. If they are tight, the guides need a light honing.
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QUESTION: Thanks Barrie. I pulled the head back off and removed a few of the springs and valves. I was surprised how dirty, and gunk-up everything was after having just cleaned it up from the previous head removal. (I only ran the engine about 10 minutes)Some of the gunk had even turned hard. Scraping it off is liking removing dried paint. I noticed this gunk/gum also in the intake manifold, and again on he valves, stems, springs, guides, etc. Is this just old crap from 30 years? Or is it from bad oil or gas??? Any help Barrie, would be appreciated. Again, I am trying to get this on the road after sitting in garage the past 15 years. I had drained the gas, refilled (added some stabil), but hadn't changed the oil (had changed it right before putting it to bed 15 years ago). Thanks.
AnswerHi Ernie. It was a mistake to run the car with old oil. After 15 years the oil will have oxidised and coated everything.
Put the engine back together, remembering what I said about cleaning the valve stems and checking that they do not stick in the guides.
Drain the old engine oil and refill the engine with a gallon of flushing oil. Do not just buy a can of additive. Run the engine for at least 20 minutes but do not drive the car, just leave it parked on the driveway with the engine running. Stop the engine and immediately drain the flushing oil. Be careful, the oil will be boiling hot. Fit a new oil filter and refill the engine with a good quality 20W/50 engine oil, preferably one advertised as suitable for classic cars. That should do it.
