Hi all:

Did a search but was not able to find exactly what I'm looking for.

First change on my 92'...read the manual & a quick 3 questions please!

1. Factory manual says do NOT use chemical flush...on my cars I usually run a Prestone flush clean on the first flush & then drain/refill water, flush more, etc. Any ideas why this flush not to be used?

2. Factory manul says add (6) cooling system sealer pellets. Will a non-solids stop-leak (like Barr's) suffice? Even Barr's recommended in Newton's "101 projects" book.

3. If I put car on my ramps so I can access the knock sensors to remove can I leave it up there during the fill/flush process? I know it will keep the air bleed valve higher than the reservoir which is good to keep the air out but any problems w/ drainage if the car is on ramps (doesn't raise it up more than I am guessing one foot maximum)?

Thanks all in advance!

JKK

 

1. Read the label on your flush and make sure it's ok for aluminum heads and you're golden. If you're in doubt don't use it. I suspect that at the time the FSM was written there were any number of flushes on the market that were too harsh for aluminum.

2. Forget the pellets. Even the dealer will likely scratch his head if you mention them.

3. Level is best for drainage but you'll be fine.

4. Yes you should go ahead and replace the t-stat now. Stant makes good ones for our cars. Be sure it's the LT1 type and looks like the one you took out.

5. You're right about the opti and keeping it dry durring this whole process.

6. Just dilute any spills so our fury friends won't suffer.

7. A shop-vac on blow is neato between flushes to get out as much stuff as you can.

 

Sounds good to me - might suggest using distilled water with a bottle of Redline Water Wetter for the final fill - otherwise good! Good motoring!

 

1. Once the knock sensors are out, it should flush plenty well with plain water. Some of the flushes have high or low ph and can corrode the aluminum heads. It's a good idea to disconnect the heater core (don't pull the hoses off of the heater core tubes, they may break) by disconnecting the hoses at the 'other end' from the core and gently flushing the core in both directions several times. The system only operates at 15psi or so and house water is more likely 60+psi so don't over do the pressure. I'd recommend replacing the 'flow control' valve that's in one of the heater hoses. About $20 at the dealer. Mine exploded and made a real mess.
2.The cooling system pellets are a bane to some but I've always used them. Some forum members reported that they are no longer recommended. The dealer has them for about $6. They are a 'vegetable' product (actually ground up peppers) so don't get their dust in your eyes or nose. It's really difficult to get 6 pellets into the system unless you grind them up and put them in the system before the water/antifreeze. And, yes, they are why you want to flush your heater core. Too much is too much. I worked in an auto assembly line (loooong ago) and can vouch that every new car gets something like these pellets or Bars Leaks.
3. Yes leaving the car on ramps is OK, in fact desirable. I believe your year has 2 bleed valves but my '95 has only 1. Don't let water leak down onto the opti-spark as you're bleeding air. Leave the pressure cap on while warming up and bleed air intermittently as it warms up. When it cools, water should draw in from the white overflow tank - leave the pressure cap on. It's something of a pain to get all of the air out. And the Helms Factory Service manual recommends 'avoiding aggressive maneuvers' until the system has been through at least 3 full cold/hot heat cycles. Furthermore, as it's warming up, watch the analog gauge and shut off if the temp approaches 260F (the boiling point of 50/50 mix at 15 psi).
The temperature will be somewhat erratic until after 3 or 4 full temperature cycles.
Hope this helps.

 

Thanks guys!

BTW...have a new stock thermostat, both new upper hose pieces, pressure cap, distilled water, & will re-route the cooling line from the throttle body while I'm in there (yes I paid $20 on EBAY for a piece of pipe w/ 2 clamps a year ago...so I was new then! haha), take off the shroud over the A/C cooler/radiator to clean out all the crap (yes, one of the "101 Projects" projects!), & take out both reservoirs to give them a solid cleaning...I think that should cover it!

Thanks.

 

with previous poster's suggestions, with some clarity.

Whereas removing the knock sensor is the ideal way of draining the block, and required if a dealer is just doing a drain and refill, if you are going to do multiple flushes, it is not needed.

Also for the price ($10-$15), suggest doing your multiple flushes with steam distilled water each time (i.e. drain, refill with distilled, run, drain, refill with distilled, run, drain, ...). This way, once the drained fluid is nice and clear, you have left only distilled water in the block, to which you can add pure anti-freeze with no concern and a perfect flushing job.

Also, assuming the current thermostat is ok, wait until the final flush/drain before changing it, that way if any coolant leaks onto the OPTI, it will be almost pure water, which is much less damaging than any percent of anti-freeze would be.

ALso, don't forget to turn on the cabin heat full -- just in case you have a valve which controls the coolant flow through the heater core.

Lastly, regarding removal of the pressure tank, there are many hoses and a level sensor underneath -- I'd suggest an alternate approach -- use a hose and a shop-vac, fill it firmly, suck it out, fill it, suck it out, until your happy -- also a baby bottle brush could be helpful if you want to clean the inside...