Hi, guys!! I have a yellow 87. My intake and value cover are leak oil in the front and back of engine. I took of my intake off yesterday and ready to put a new intake gasket back on. Since the intake is off now, here are my questions:
1. I see there are some ideas about the gasket installation. It is confusing to me about the right procedure. What is the best way to do it? For example. someone prefer just put the gasket with RTV in the front and the back. others like to put a thin RTV around the gasket where the coolant runs through. If this is good idea, which side of gasket should I apply RTV? Is it hurt if I put too much RTV in the front and back of intake?
2. Someone prefer tighten with low torque (2-8 pd-ft) first and wait for RTV to dry for 24hrs and try to torque down to the specifics (35 pd-ft). Someone prefer to retorque to specifecation after a few heat recycle. This might require to take everything apart again.
3. but my friend told me he did not apply any RTV on the gasket except the front and the back of intake. He torque the bolts to specification. His havn't experience any leak so far. This is the same step which I saw in my corvette service manuals. In Haynes manuals it told you to apply RTV around coolant area. I am really confuse? Which one is the standard/best way to do the job.
4. What's different red and black RTV? Which one should use to the front and the back of intake? Can I use them for thread sealer to seal intake bolts?
5. what other components better to be replace other than thermostic? (i.e. feul injector, spark plug, .........etc. By the way I can't find the fuel filter)
6. should I flush my cooling system? How to do it? Which thermostatic should I use 160, 180, or 195 degree? What's the different?
7. should I replace my automatic transmission oil? How often should I replace them?
8. When is the first oil change after the intake job?

Sorry to ask so many questions. I just own this corvette. I try to do my best. :seeya. Thanks so much!!!

 

Hey me too! :D

1. I smear a very small amount of RTV around the passages and some on each end to keep them in place. I hold them down with my fingers for 30 seconds to set them. I also put a good sized bead of RTV on the front and rear china walls and let it sit there about 2 minutes before dropping the intake down. You don't want so much that it'll squish and fall off into the lifter valley. That will just end up in your oilpan and at worse in your oilpump and gum things up.


2. I torque them in 3 steps all at once and then let the engine sit 24 hours. SO FAR they've been torqued the same when I take it off thousands of miles later.

3. Its personal preference really. Both work, but why not add a little bit of protection JUST in case?

4. I use black sensor safe RTV everywhere for sealing. As for thread sealer for bolts that go into water jackets you'll want to use white teflon paste.

5. Well maybe a PCV valve, EGR valve if you feel like it, oil pressure sending unit would be great since you actually have access to it now and they do seem to fail with old age. The fuel filter is located underneath the car along the right frame rail sort of near the front y-pipe. You have to remove a small aluminum heat shield held in place with 2 screws to get at it. Then you'll need line wrenches to get it off.


6. I would drain as much as you can and refill. I run a 160* thermostat personally. This means at 160* the thermostat is fully open and allowing coolant to ciculate through the whole system. My car runs about 185* in summer with this one installed.

7. If you don't know the last time it was, yes have it flushed for peace of mind.

8. It wouldn't hurt to run some cheapo oil for 500 miles and then swap it and the filter out.

Good luck. :seeya

 

Assuming (I’m not positive) that your ’87 is the same as my ’89,

The fuel filter is on the passenger side under the car just behind the front wheel by the gills on your side panel. It is covered by a metal shield that is held on with two 10mm bolts.

As for the RTV, you should use the “Right Stuff” made by Permatex. Put it on the front and rear of the intake as well as around the coolant passages on both sides of the gasket. Put a little around the coolant passage then stick the gasket on then put a little around the coolant passage on the gasket itself.

You don’t want to put toooo much RTV on there, I think the norm is about 1/8” steady bead. Make sure you clean all the old gasket residue off before you put the new ones on.

I changed my fuel injectors and thermostat when I did my intake manifold because I was there so I figured I may as well do it. You should also probably change all your runner and TB gaskets as well and clean your TB.

As for the bolt torque procedure, you should torque the bolts in equal stages, I did 7#, 20# then 35#. Then I let the car sit and setup overnight, then the next day recheck that they are still at 35#. Do you know the proper sequence in which to torque the bolts? This is very important. If not, somebody else will need to give you the sequence because I don’t know that ’87 and ’89 are the same, and I don’t want to give you incorrect information that is so important.

I have a schedule to change my trans fluid every 15,000 miles. I changed my oil before I started the car after the intake gasket change, I don’t know if this is necessary but it was time anyway.

I use a 195* thermo in the winter and a 160* in the summer, you should be fine with a 160* in Tucson. (There is a huge debate here on the Forum about which thermo to use).

Oh and BTW, welcome to the Forum! :cheers: :seeya :thumbs:

 

I would reccomend purchasing a Helm shop manual for the car. This is the same book the guys in the dealerships use. It will decribe exactly what you need to remove to accomplish any job and how to reinstall.
I think they are at http://WWW.helm.com

If you put RTV around the coolant ports you need to put it on both sides of the gasket....not too much. You only need a bit to do the job.
This is reccomended to limit the likleyhood of coolant leaking at the gasket.
If you don't do this, it may or may not leak.

I think the Helm manual states to torque to 18ft lbs IN THE SEQUENCE INDICATED IN THE MANUAL and the do a final touque at 35 ft lbs. You don't need to wait 24 hrs.

The manual also states to apply a 3/16 bead of RTV on the froward and aft ends of the block where the intake mates and extend the bead 1/2 inch onto the intake gasket.
Too much RTV on the front and back and it will leave a flap that is susseptable to leaking. Not enough RTV will also eventually leak.

Note that cleaning is absolutely crutial. Scrape surfaces clean of any gasket material then abraid with scotchbrite. Finally, thoroughly clean all mating surfaces with MEK.

Wait 24 hours for RTV to cure before starting the motor.

Your fuel filter is under the car, on the right side near the passengers feet.

I'd suggest contacting a shop for your coolant and trans fluid change.

 

Keep in mind the torque settings WILL BE DIFFERENT depending on what you use for sealer and what bolts. For exmple my ARP hardware uses different specs depending on if you are torquing with ARP thread sealer or engine oil.