Andicog
Member
- Posts
- 53
- Location
- Merseyside
Right, bit long winded this but stay with me! I had a bent rod replaced, fuel pump rebuilt, new cam belt, woodruff key and head gasket, all going well though it always sounded slightly noisy on one tappet, fast forward a couple of thousand miles and I start to get a bomp bomp noise from the air intake, reading up I found that this could be valve clearances, I checked and sure enough they are all pretty big, well over 1mm, worse is that 2 of the M8 rocker shaft bolts have backed out and both the small rocker shaft locating bolts have gone, I find one in the oil on top of the head, I call company that did the work and they recover it after advising me not to use it with missing rocker shaft bolts as they may be in the oil feed.
They tighten down the M8 clamp bolts and replace 1 rocker shaft locating bolt, they say this engine only has the one locating bolt, they reset the tappets and I'm away again, still sounds tappety especially on one tappet but runs well.
Now after another 1000 miles I check the tappets, engine is warm, all are uniformly large, one being worse as the valve stem has lost its cap, I reset them, even though one is missing a cap and order the parts, a week later I come to fit the missing cap, the valve clearance on the capless valve is pretty big again but I fit a new valve cap and reset all the tappets spot on to 10 thou with the engine cold.
It now runs like never before, quick (ish) and smooth, what's bugging me is why the gaps had opened up in the first place? Are the rocker shaft location bolts in an oil feed? Has me using the engine with them missing starved the followers and lobes? Is the garage right, should this engine only have 1 locating bolt? They say they set clearances both times to. 25 mm. Since I've set them 2 days ago the engine is nice and quiet, responsive as well, just hoping it stays that way!
They tighten down the M8 clamp bolts and replace 1 rocker shaft locating bolt, they say this engine only has the one locating bolt, they reset the tappets and I'm away again, still sounds tappety especially on one tappet but runs well.
Now after another 1000 miles I check the tappets, engine is warm, all are uniformly large, one being worse as the valve stem has lost its cap, I reset them, even though one is missing a cap and order the parts, a week later I come to fit the missing cap, the valve clearance on the capless valve is pretty big again but I fit a new valve cap and reset all the tappets spot on to 10 thou with the engine cold.
It now runs like never before, quick (ish) and smooth, what's bugging me is why the gaps had opened up in the first place? Are the rocker shaft location bolts in an oil feed? Has me using the engine with them missing starved the followers and lobes? Is the garage right, should this engine only have 1 locating bolt? They say they set clearances both times to. 25 mm. Since I've set them 2 days ago the engine is nice and quiet, responsive as well, just hoping it stays that way!