I have a 98 I30 (basically a Maxima GLE) that had it's 30K service recently at my local Infiniti dealer. Only the coolant in the radiator was replaced even though he charged an hour labor and claimed it was a flush. I have complained to Infiniti and they are standing behind the dealer who claims that is all he can do since he does not have a power flush machine.

I also have a 90 Q45 and I know that it has block drain plugs which are supposed to be removed as part of the cooling system service. I have the service manual for the Q45 and it specifically calls out the need to do this.

I have talked to my local Nissan dealer and they claim to do a complete flush of the cooling system, not just a radiator drain / fill. My Infiniti service manager told Infiniti that they are lying and can do no more than he did without a power flush machine.

Does the Maxima / I30 engine have block drain plugs?

Does anyone have a service manual for the 95-99 Maxima (or I30)? What does it call out for the coolant service? Is it simply draining & refilling the radiator or does it say to pull the block drain plug(s) as part of the service?

I am quite upset that the dealer has done such a poor job of servicing the cooling system. At most only half of the coolant was replaced. I am also upset that Infiniti does not really care about customer satisfaction.

 

Yes, two of them.

Perhaps the answer to your questions is right in your glove compartment. Chapter 8 in the '99 Maxima Owner's Manual is titled Do-it-yourself. It provides detailed instructions for changing the engine coolant. The procedure calls for opening the radiator drain plug and two drain plugs on the engine block. Three line drawings depict the location of these three drain plugs.

 

I don't think you need a "power flush machine" to flush the cooling system. All the dealer needs is a water hose! The Haynes Manual has a good descripton of flushing using a garden hose. After a coolant change, pay close attention to your coolant level. Generally it is advisable to make sure the overflow tank is maxed out after the change, as there can still be air bubbles left in the system after the flush.

I just had my coolant flushed a month ago and when I got my car back, the coolant overflow tank was completely full (just below the spillage spout). I drove the car around for a week, used the heater, and the coolant level is back to normal again.

BTW, did your infiniti dealer remember to drain the coolant from the heater core also? All you have to is turn on the car and set the heat to maximum (that opens the heater core up to the engine coolant). That way when the coolant is drained, so is the heater core.

 

I've been there and done that twice now on my 96 Maxima.
First off, the procedure outlined in the owners manual and factory service manual calls for opening the block drains (2), which is nearly IMPOSSIBLE without removing the factory exhaust y-pipe. Believe me, I tried to get at them from every direction. The front block drain was reachable, barely, to loosen, but it became apparent that getting it's threads restarted after draining would next to impossible without removing the y-pipe. The rear block drain is inaccessible without removing said y-pipe.

Second off, it is unnecessary to open the heater control valve since the 95 to 99 Maximas don't have one. They use an air blend heater that has the coolant running through it at all times. Flapper doors blend air for the desired temperature.

To actually change the coolant, I used the method I've used successfully for many years if block drains are not accessible, and that is to first drain the radiator, then refill the radiator with pure water, run the engine for a few minutes until the radiator thermostat has opened to mix the coolant from the block with that in the radiator, then re-drain the radiator repeating these steps six or seven times until the coolant drained appears clear. It takes awhile. Then after the last radiator draining, add to the radiator, pure antifreeze, in the case of the Maxima, 4 qts. and 2 oz., and top off the radiator with pure water. Then remove and drain the overflow bottle and refill to the "H" mark with a 50/50 mixture of antifreeze and water. Follow the procedure in the owners manual or FSM for venting air out of the system by running the engine and rechecking coolant levels. This method will result in a fresh 50/50 antifreeze/water mix in the entire cooling system without having to deal with the block drains. It's no wonder the dealers without coolant flushing machines only drain the radiator. I doubt if they take the time to make sure all the old coolant has been remove either.
-Mark Paar

 

Thanks to all.
That is exactly what I was looking for.
I found the procedure in the owners manual and made a copy.
I had asked my service manager about them on my Q45 and his exact response was "do you know how hard they are to get to?". I guess it is the same with the Maxima / I30. Still if they charge me an hour of labor and put "flush / fill cooling system" on the bill it should be more than just a radiator drain & fill.
I had an idea of my own on this. Why not drain the radiator, refill with water, then remove the upper radiator hose & run the car. As far as I can figure that would flush the whole block since the cooling system pulls coolant from the bottom of the radiator & returns it to the top. I suggested this to the Infiniti service manager & he said "do you know how much pressure there is?". But when the sytem is open the pressure is minimal, only high pressure when closed and HOT.
If the procedure in the manual is too hard for the dealer to do, they should not print it as DIY instructions!
Thanks again to all.

 

MarkP, thanks for this info. I spent about an hour under my car a month ago trying to figure out just how I was going to get to those drain plugs. I also agree with Q45-I30, why list it in the diy section of the owners manual if it is an impossible task. I like you idea, slow but certainly would take care of it.

Thanks for the info.

 

Don't pull the top radiator hose. You can wind up with too little coolant in the system and localized overheating: very bad. What I do is:
1 - open petcock on radiator and drain it
2 - with petcock open run garden hose into top of radiator and let hose run until clear water runs out of bottom of radiator.
3 - close petcock, fill radiator with water, leave radiator cap off and start engine (keep filling radiator with water until full)
4 - after several minutes, open petcock and run fresh water in top of radiator (with engine running - this will flush block)
5 - shut engine, let radiator empty then refill with pure anti freeze
6- replace radiator cap, start engine and loosen top bleed bolt
7 - refill overflow tank as necessary

I wouldn't worry about getting every last bit of old coolant out. Just drain and refill radiator every year with 50/50 mix.

 

On the Maxima, the water pump sucks from the UPPER radiator hose via the thermostat when it is open and the coolant bypass when the thermostat is closed. The UPPER radiator hose is actually connected to the bottom of the downflow radiator on the passenger side end of the engine. The LOWER radiator hose is on the drivers side end of the radiator at the top.
This flow is backwards from most other automotive systems that have the water pump suck from the lower radiator hose that actually connects to the bottom of the downflow radiator. Confusing maybe but that's the way it is.

By removing the upper radiator hose as you suggest, you would allow the water pump to suck air. Removing the lower radiator hose (on the upper drivers side end of the radiator) you would empty the system fast until the pump lost suction but you would not remove all the coolant from the block as centrifugal pumps don't pump once they have lost suction. Nice thought but I'm afraid it wouldn't work.
-Mark Paar

 

it certainly works. And back in the days of my environmental irresponsibility I would do it your way. But now-a-days I try to collect as much of the old coolant as I can in old milk jugs etc. to take to the recycles and try to minimize the amount needed to be collected. That's why leaving the hose running to flush the system as the radiator drain remains open has it's draw backs, because of the greater volume of liquid.

-Mark Paar

 

Just a stupid question, but I am curious what happens if you don't ever change the fluid??

 

brubenstein,

Don't you think that running cold watter from the hose into the hot engine not such a good idea??

 

What brubenstein is suggesting doesn't heat the engine enough to be a problem when running water through the radiator. He is only saying to run a small stream of water to replace what is drain out the petcock. I've done it many times myself.

-Mark Paar




[/I][/QUOTE]

brubenstein,

Don't you think that running cold watter from the hose into the hot engine not such a good idea??
[/I][/QUOTE]