I have a 22R and would like to know if there is anything I should be aware of before starting a head gasket replacement. I have a 87 4X4 pickup 22R with water leaking into a cyl. no previous overheating. I have seen a few comments on corrosion and the problem it presents trying to seal the water jacket. I have changed the coolant regularly and I am the original owner. I'll start this project in about a week so any advice on "typical" problem areas would be appreciated.
"Jerry" wrote in message news: snipped-for-privacy@posting.google.com...
First off, sorry for the long-windedness.
These 22Rs warp the heads really easily. Once you get the head off the engine, there will be no spring tension on the cam (rockers come off after head bolts). Try and turn the cam with your fingers (not using the gear). If the cam turns easily and freely throughout
360 degrees of rotation, proceed. If the cam binds at all, the head is warped or the cam is warped, or both. The most likely is the head. Next, mark the bearing caps with an arrow toward the front and 1, 2, and 3 or Front, Middle, Back... however you like. Remove the six screws holding the cam. Take the bearing caps off. Wipe them with a clean clean lint-free rag and check for damage... better yet, spray some sort of solvent on them to wash them off, then blow them off with compressed air. On one of my engines, the middle cap was broken... watch out for that. Lift out the cam. The surface tension of the oil in the journals will tend to want to keep the cam in the head, so be careful. Maybe even wear some gloves to avoid sharpness. Definitely try not to pry on it or remove it unevenly.. Check the bearing surfaces of the cam and the lobes as well. Inspect the journals in the head. If you see any scoring or pitting .. time for a new casting. If the warped, buy a new head. Don't make the mistake I made. I brought my head to the machine shop.. I think they resurfaced it before they even checked out the cam (which is why I mention it to you). They found the middle cap broken and the cam chewn. "We can [align] bore it for ya and drop in a new cam" says them... Foolishly, I agreed. Got the piece of crap back and the cam would not turn *AT ALL* when torqued to spec. I even put the gear on and put a wrench on the cam gear bolt... NADA... The head was so warped, the cutting tool used to align bore the thing did not touch the middle journal at all even after cutting .0005 ... Brought it back and the "owner" of the place said "welllll, I dunno how freely that cam's supposed to turn.." It should turn like butter or it's F****D. I ended up taking the advice of a race-prep shop here in town to remedy the situation...The dude on the other end of the phone told me my best bet, short of a new casting, would be to find a socket the size of the cam journal, a piece of
400 wet or dry sandpaper, and a dish of kerosene (to keep the paper from loading up with aluminum) and set about sanding away at the middle journal till the cam turned with slight resistance. You wrap the paper on the outside of the socket and figure out a way to evenly sand the thing.. Finally, I got it. I don't remember how many miles I have on the thing now since I put it back together, but it has been quite a few. Lately, I am getting a recurring air bubble in the cooling system. I burped the thing twice in the past couple weeks, but it still comes back with an air bubble after a couple days... regretting not buying a new head, once again.
If your head passes the visual inspection of the cam journals and the cam, take the head to a machine shop that you trust and have them pressure test it. If it is warped or cracked, my advice is to buy a new head. You can get a new, complete head from a user on Ebay. His handle is 'engnbldr'... search for him on there if you are interested. I have bought parts from him
3 times and every time, he gives me the right parts at a decent price. If you go with your old head, I recommend replacing the valve springs and the valve guides at the very least. You may be able to get away with re-facing the old valves, but I would just buy new ones for 5 bucks each... ~5 bucks will get you a Hollywood valve. Do not be talked in to knurling the old valve guides. This is a shadetree practice if done on old guides. New, Hollywood guides are $5 each as well.
Last but not least... if you are sticking with the old head, do yourself a favor and heli-coil the 6 holes that the cam screws go into and heli-coil the hole that the distributor screw goes into before you put it back on the car (or ask the machine shop to do it and tell them you will gladly pay for the extra measure)... it's worth doing. I had to take my head off again because two holes stripped... and now that the whole thing is back together, the distributor screw is getting dangerously close to eating all the threads in the hole.. :(
I forgot to mention that if you want to put the cam back in the old head, make sure the caps, journals, and bearing surfaces on the cam are completely clean... pour 30w oil on the bearing surfaces of the cam. pour 30w oil on the cam journals in the head (make sure you get the thrust surfaces on the front journal as well). Lay the cam in the head. Pour 30w on the bearing caps and reinstall in the proper position. Put the screws back in and tighten in stages to proper torque. Make sure the cam doesn't bind by turning with your fingers after torquing. If it binds after retightening and it didn't before, then there's trash in the bearings or it's torqued too much... back off, remove the cam, check for trash, and try again.
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.