Hi all - I'm refreshing and powdercoating the intake on my 88, and I took the valve covers off to have them powder coated as well. Since the valve covers are off, is there anything in particular I should look for or do? Everything looks in pretty good shape, but I've never had the valve covers off before so I am not sure what to look for. Thanks!

 

Aside from the valve cover seals you could replace the pad on the chain tensioner. Be careful of the oil return drain holes at the base of the heads. Dont want to drop anything down there. If you plug them up W/ paper towles double check to remove them before putting the valve covers back on.

 

if your doing the intake then you should replace all of the parts I am listing
both knock sensors, the throttle position sensor, the crank position sensor, the Hall sensor, the flappy shaft bearings (keep the rubber seal facing away from the intake, to keep out dirt), the flappy vacuum pot, the idle stabilisation valve, the O ring for the oil, fill housing (unless you can see it is deformed then the whole housing), all the fuel lines ( there are 4 of them )
OPTIONAL to upgrade to the 4 hole Fuel injectors, both fuel dampers and the pressure regulator

For the cam covers there should be sealing washers that fit underneath the cover bolts and between the metal washers these add a bit more crush to the bolts there are 6 per side along the bottom edge of the covers, I would recommend that you add these washers to all of the bolts they are aluminum.
Also add some sealant to (Yamabond will work) to the cam cover seals where the covers meet the cam caps you should see old sealant when you remove the covers.
You will want to also replace the O rings on the breather tubes that come out of the covers and also the block offs.
Also look at the timing chain tensioner pads, some wear is OK but if there almost worn through then they will need to be replaced, check the timing chains and the teeth of the cams for broken teeth.
If you replacing the end seals they are blck and about 2 inches in diameter then you can loosen the cam cap bolts about 3 turns then pry the old ones out and install the new ones then tighten the caps back down.... Is this too much??

OK you should also remove the water crossover bolts and clean them and reseal the crossover to include replacing the thermostate and the black sealing ring behind it, make sure to put anti seize on the crossover bolts. If you coolant tank is yellow or brown now is a good time to replace this as well also consider replacing the washer fill tube and if you do this then remove the metal rings inside the tube and the tank. had enough yet??
Ok replace the heater control valve and short hose to the head.

All of this ought to get you another 15 to 20 years

 

Thanks for the suggestions guys. Greg - what would point to a worn chain tensioner? From what I can see they look in good shape - I'd rather not mess with them if I don't have to, but if that is something that should be replaced I'll make the effort for sure.

Mrmerlin - wow - thats an exhaustive list - lol. But exactly what I was looking for - the '88 hits 20 years old this year, and I'd like to plan not to have to do this again until 2028 . I've got most of the stuff you mentioned planned, but you hyave me a few other ideas since everything is pulled away.

On the 4 hole fuel injectors - what would be the benefits over the stock injectors? More power or less concern of an injector clogging?

Thanks again!

 

Powder coat the water manifold as well, it falls out of tune with al the other items shining at you when you're all done!

 

The chain tensioners have 2 pads as can be see in your photo. The drivers side the tensioner applies pressure to the top of chain and the passenger side to the bottom of the chain (hope that makes sense) anyhow the pad that is applying the tension will often get a channel worn into it by the chain. It should be pretty noticeable as it was with my car, the other pad (non tension side) should look much better.

I only replaced the pressure side pad and left the no-pressure side alone. I am not sure if it is a good guide to when to change the pads but they are originally white IIRC and become orange and brown like yours over time with heat, oil and age.

Good luck Bill, hope Calli is treating you well!

Michael

 

What Michael said. You can push down the piston on the tensioned side and get a look as to wear. The other side will have the tensioned side facing down and you will not be able to see it unless you remove the tensioner. I know this sounds confusing, but once you look at it it will make sense.

 

Oil Check Valves. One in each head. You can replace the o-ring and the springs. See WSM for removal procedure.

 

Did anyone mention obvious yet? Talking about 2+3=5 oil plugs at rear of the heads.

Also I would try to remove piece under oil check valve. If it comes out easily without damaging it or head I would replace entire check valve assembly with 944 S2 3 bar valve setup.

 

anything and everything that is rubber... all new seals on valve covers, injector seals, u-shaped fuel line on back

 

4 hole injectors seem to offer a bit more performance since they are atomising the fuel into smaller droplets. I noticed a big difference in starting and then throttle response, and since your old injectors are 20 years old why not splurge, with a new set, you will need new O rings for the lower injector seal as the ones supplied usually are made to fit the Ford Mustang 5.0 they are 19 pound injectors

 

I have just completed every item that Mrmerlin listed except "the check valve assembly". My engine is still out so...
Could you elaborate a little more on this change.
Thanks

 

don't forget vacuum lines and fittings (but be aware of the Mark Robinson kit - do a search of the issues with his fittings - Roger has good replacements)

 

there are oil cherck valves in the corners of each head they are held in place with a small setscrew installed from the side of the outside of the head.
This removes a top plug with an O ring on it and then undernea this a spring and a ball, the most important thing to check for is the seat that the ball sits in, if its loose then it can get pushed up and effectivly block off the oil passageway to the cams/lifters. Then your belt will snap after the cams seize in the head

 

Good tip on the seat. I did not check that. I did clean and relpace the "O-Ring" and all looked good. Next time I am in there I will check the seat.

Is this seat what Vilhuer is refering to when he writes of a 3 bar 944 replacement ?