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[Thunderchild]

Afternoon all.

Today I removed the rocker covers and discovered that there was a lot of iron swarf in the exhaust rocker. Closer inspection showed that the oilway into the rocker was blocked by swarf and that that the rocker was dry. It appears that the exhaust rocker arm had 'eaten' into the rocker bearings; there was significant wear where the rocker arm interfaces with the rocker bearing. I noticed that the inlet rocker bearing is also worn but not to such an extent.

I've cleaned out all of the swarf with a magnetic tool and cleared out the oilways. The oilway inside the exhaust rocker bearing was clogged with swarf.

I'll renew both rocker bearings but is it normal for the bearings to become worn? All the connections in the rocker area were tight.

Thanks,

Andy

[Paul M H]

Sounds like it might be Oil pump failure too me I would check for flow at rockers and check the oil pump worm and drive its probably toast but will definitely need checking.

[Gwilly]

Well i never, i can't say i've noticed a plague of rocker bearings going west so suddenly but all things enfield are possible.

How many miles has the motor covered? Has it been rebuilt and not flushed and cleaned properly before reassembly.

Just wondering which came first, the wear or the swarf... There is a mod whereby the oil hole in the bearing is drilled out to bigger diameter.

something like 2-3mm but cant remember, please check.. someone here will know i'm sure.

Oil change and wash the filter in jar of parraffin check for swarf at the bottom of the jar... best of luck, gwilly.

[Thunderchild]

Gents, an update. I noticed that the inlet rocker was very dry so investigated further; the oil pumps were not operating so no oil was being pushed to the head! After pulling the timing cover I found that the oil pump spindle was very worn and the worm nut thread had snapped off in a few places. It appears that this is the root of my issue. I've ordered the necessary replacement parts from our hosts and will begin rebuilding. Many thanks for all your assistance and hopefully if others have the same issue as I, they will check oil flow first!

Andy

[Norm]

Big end is failing, the swarfe found in the rocker blocks will be whitemetal that can't get through the rockers and blocks solid therefore loading up the pump spindle and because there is no relief valve the pump spindle eventually strips so therefore you think the problem was caused by pump failure but the proof is in the fact that the whitemetal is in the rockers proving the pump was still working because there is no other way the whitemetal can get there unless pumped. Sorry, don't fit the new bits or you will be replacing the pump spindle a second time

[Thunderchild]

Norm, the ends of the inlet rocker box were badly worn where the arm had eaten into the metal. The box was also dry indicating that no oil had found it's way up to the rockers. The swarf was a grey colour, due to mixing with oil. I think the metal in the rocker was the remains of the rocker block. I dropped the engine oil and didn't see any metal in it. There had been no signs that the big end was going i.e. knocking noises.

Andy

[Phil Ashbrook]

Is the grey sludge magnetic ?

[Phil Ashbrook]

I realy dont know how long the big end can go with no oil but it must have started touch ( big end shells or bush need oil to keep them apart so they float , if at any point of break through they touch a score will develope that in it's self heat and tear , at best you might have taken years off it or maybe she will go after the re-build , think speedway , pull the crank apart and inspect . Roller bearings are more forgiving and with domestic use can last a very long time , I know pulling the crank seems heavy when you could just replace the spindle and worm and at worst your tappet guides ( thats a bit of a job really , blow torch stuff ), I think it's possible to fit a pressure sensor to warn of pump fail ..I just pull my cover off once a year , I'm using a new Indian spindle with a British neoprene worm .
My trick to stop kick back damage is not to tighten the worm very much as it's a L/H thread and the spin of the engine keeps it tight but if it should kick backwards it can break free and normal direction will re tighten it again . This prevents damage .

[Norm]

Ok so was there any swarfe in the oil slots in the rocker blocks and the oil hole in the bottom of the blocks?

[Bullet Whisperer]

Hi Andy, Check the filter at the front underside of the crankcase [looks like a drain plug]. If this is clean, it means nothing is likely to be breaking up inside the bottom end, or even the piston, rings etc, as all oil from the crankcase is sucked through this by the scavenge pump. If any of these components were breaking up, this guaze filter would catch the debris and it would be there for you to see when you take it out to check. If it is clean, the damage is from further along and easier and cheaper to fix and possibly from the rocker blocks themselves, as you say. On the downside, a broken oil pump drive will make all areas of the engine starve of oil and the rocker blocks would suffer as you describe, but the big end could also suffer damage in this situation. You could sort out the rockers and oil pump drives and run it for a couple of miles, then pull the crankcase filter. If it is clean after this, you should be ok with it, but any swarf will indicate more trouble on its' way and possibly a full rebuild needed soon, but you will have already sorted the rockers and oil pump drives, at any rate. Cheers, Paul.