Top engine taken apart and I've got question

[splitz]

In my previous thread it was suggested I go to the skool of hard knocks to learn to wrench. Well I've started my first class with a valve adjustment. While I don't have any questions on the adjustments themselves (yet) I do have some general engine questions:

1. Is there suppose to be gaskets on both sides of the coil covers?
2. What is the part number for coil cover bolts? I didn't loose one, one was missing.
3. The brass stems that you remove off of the top of the valve covers on the front were lightly oiled, while the rear were dry and oxidized. Is this ok?
4. What do I look for to know if the spark plugs need to be replaced? Here's a picture of them. Attached pic #1.

5. If I were to replace the cams would it be as simple as removing the two brackets that the red arrows are pointing to? (Not that I'm seriously concidering it, but then again...)

Thanks for your help everyone!

 

[Daedalus]

Wow, you don't F- around. I thought the recommendations regarding the school of hard knocks were related to a beater car. 1st lesson is to get intimately familiar with the sections of the FSM you want to learn about. 6-23 in the '91 manual answers question #1--there are single seals on the intake sides of the coil covers only.
2. There is a parts catalog in the Reference section.
http://www.nsxprime.com/FAQ/Reference/1991-1992_parts_catalog/1991-1992_parts_catalog.htm
http://www.nsxprime.com/FAQ/Reference/1991-1992_parts_catalog/1-c1.jpg
I think FN 18 in the 2nd link is the part you need.
3. Sounds like a bad seal/gasket.
4. Modern plugs are replaced based on mileage intervals. I would say yours look a little fouled but not bad. The NSX seems to run richer than most cars at low RPMs. In the old days you would inspect the gap, but it's not recommended because a) plugs today are very durable, b) checking the gap raises the risk of damaging the very durable but thin platinum coatings, and c) setting the gap even moreso risks damaging the platinum coatings.
5. Again love the FSM, specifically page 6-33 for the '91. The cams are under the perpendicular cross pieces that are under the parts you indicated.

Like others said in your other post, it's called the school of hard knocks for a reason. Be very careful. Take good notes and lots of pix. If you get frustrated with something take a break.

 

[Daedalus]

I have a question for you: Has the engine been apart before that you know of? The missing bolt reminded me that my car was also missing a bolt on one of the timing covers, but the previous owner had no knowledge of the timing belt ever getting done. Belt looked fantastic, but the water pump was original.

 

[Kris]

Not as simple as it may appear, to do the Cams, you gotta put the crank to TDC, loosen the timing belt tensioner, take the timing belt off the cam gears and take off the cam caps and they're out, then put the cam gears on the new cams and stick 'em back in...then you gotta torque everything down to spec and in the right order and don't forget your honda bond where needed. I think I got everything.

 

[Hugh]

You really should pick up a service manual for your car. You can order one from Helm.

 

[splitz]

4. Modern plugs are replaced based on mileage intervals. I would say yours look a little fouled but not bad. The NSX seems to run richer than most cars at low RPMs. In the old days you would inspect the gap, but it's not recommended because a) plugs today are very durable, b) checking the gap raises the risk of damaging the very durable but thin platinum coatings, and c) setting the gap even moreso risks damaging the platinum coatings.

Unfortunately I am the third owner and have no idea if the plugs have been replaced or not. The guy said he and a buddy did the 60k service, but the air filter was filthy, so I am really skeptical.

I have a question for you: Has the engine been apart before that you know of? The missing bolt reminded me that my car was also missing a bolt on one of the timing covers, but the previous owner had no knowledge of the timing belt ever getting done. Belt looked fantastic, but the water pump was original.

I don't know. While the previous owner said he did the 60k, the valves are noisy as hell and the air filter was filthy.

Not as simple as it may appear,

Nothing ever is. I MAY do some more research on this, we'll see. How beneficial are new cams?

You really should pick up a service manual for your car. You can order one from Helm.

I agree, it's on the way!

Thanks for your help guys.

 

[ktan]

In regards to the noise, your valves probably just need to be adjusted. Its a long tedious task (IMO) but at the point where you are at, you are ready to do the adjustment as long as you have the correct tools (feeler gauges for intake and exhaust and valve adjustment tool (10mm) )

I've heard that the factory cams are very well engineered and aftermarket cams are not necessary (besides the high price of them ... def in the $ thousands. Doing cams in the car is a LOT of work when you consider the timing belt side of things, hell its even a pain OUT of the car!

 

[splitz]

Ok, new question. When I am turning the Crankshaft pully why are some cylinders harder to turn than others? I find that 1 & 2 are relatively easy, but 3 & 6 seem very hard! Is this normal?

 

[britlude]

are all the plugs out/loose? remember you are turning the engine and some cylinders will be on the compression stroke...

re. sparkplugs: if you're worried, replace them and keep those for spares! you know, the type of spares that clutter up the garage, never to be used, but always handy 'just in case'!

 

[splitz]

are all the plugs out/loose? remember you are turning the engine and some cylinders will be on the compression stroke...

re. sparkplugs: if you're worried, replace them and keep those for spares! you know, the type of spares that clutter up the garage, never to be used, but always handy 'just in case'!

Yeah, after I posted that and thought about it I put 2 & 2 together and realized the easy cylenders to turn were the one w/o the plugs in em! Go figure :smile:

Thanks for your input!