Cleaning rocker assembly and top of heads in situ?

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.

JamesBB

Active Member
Posts
754
Location
Bugley, North Dorset
Hi All

I have a 96 P38 4.6 and am changing the valley and rocker gaskets as I have an oil weep that is making a bit of a mess in places and started to smoke a very little on the rear of one bank is it drips on the exhaust.
While in there I have noticed that despite regular oil changes with name brand oils I have a little sludge build up on top of the heads around the rocker assemlies. Nothing major, but using a plastic scraper can easily get it off.
I would rather not take the assemblies off as I plan for a new camshaft and followers maybe in the next year (nothing wrong just old and a little worn), plus the main dirt build-up is clear of the moving parts.

My question is, what is the best way to clean this off while leaving the assemblies in situ as a temp job until I do the more extensive work?
Degreaser, small brush, plastic scraper? Then change the oil afterward?
Inside the valley itself seems clear of any real dirt.

Thanks
James
 
I'd go with marjon on this.
Gave the top end of my 3.5EFi a going over a few years ago incl new camshaft & followers, timing chain and its crank & cam sprockets. Heads off and clean up of valves plus new springs. The valves & seats were in very good condition with very minor pitting on the exhausts which easily cleaned up with fine paste on a hand operated stick.
When I cleaned the rocker assembly I removed the bits one at a time, cleaned them and then put them onto a length of dowel so they remained in the same order for reassembly.
Lots of crud inside the rocker shaft.
Lots of crud in the oil passages of the arms themselves, some of which needed poking out before flushing with a aerosol of 'clutch and brake' cleaner.
 
Got any pics?

Personally, If you are planning major surgery next year I wouldn't bother, with the possibility of hard crappy bits getting into the system where you dont want.

J
Cheers
I have already wiped over the rockers and looked a little closer at the dirt build-up. I do not think it is too bad, like you say wait until the major surgery comes.
Here are some pics anyway.
ROCKERS.png


Does it look like the oil holes/ports are clear enough?

BTW, this is the original engine with 150000 miles on it.
Thanks
 
Doesn't look bad at all.
You can't see the passages in the rocker arms in situ. They need to be taken off.
 
Looks a lot cleaner than Otto's heads / rockers were when we took them off as the head gasket had blown. Can recommend either Gunk green or Autoglym engine and parts cleaner / degreasant - do a stunning job and no fumes.

Strip and clean in order as @Ratae says above, or strip and keep in order in a compartmented tray, then clean 1 part at a time and do reassembly. Posts can be a very tight fit on the shaft, I found they went together much easier by freezing the shaft for half an hour or so and heating the pillars to about 150C in the oven. Fractional increase in clearance makes a big difference for getting it back together. If you do that start with one of the inner pillars do the central rockers / springs, other inner pillar then the ends. Much easier than going all the way along the shaft if you start with an end pillar.
I don't know if it is necessary, but having only WD40'd them on assembly I plan to try to prime through the shaft before putting them back in for start up.
One cleaned, one still as removed.
 
Back
Top