1996 850 Turbo Wagon
2.3 L - 165,00 miles

Hi all,

It's time for a new timing belt.

At this time I am going to put in the following:

1. Timing Belt
2. Timing Belt Idler Pulley
3. Timing Belt Tensioner
4. Tensioner Damper
5. Water Pump
6. Thermostat

I plan on putting in Genuine Volvo parts unless others on here suggest something at least as good or better by another manufacturer at a cheaper cost. I do not want to scimp on quality for these type of parts.

I plan on putting in distilled water and Zerex G-05 Anti Freeze back into the system when done.

While I am doing all of this I figured it would be a good idea to flush out the cooling system to get out the crud and rust in the system before putting in a new water pump, thermostat and coolant.

At this point there has been no cooling problems or issues with the car. This is more a preventative maintenance procedure. Any thoughts?

Flushing Procedure If Recommended:

Drain the coolant from radiator petcock. Drain the engine block by the drain plug. Pull the thermostat and flush with a hose to clean out as much as possible.

Close block petcock. Close radiator petcock (IF using flushing agent). Put the thermostat housing back on minus the thermostat and run car to circulate flushing agent. I would use plain water for this flush type. Drain water again through radiator (and block petcock?) and fill with distilled water after installing new thermostat.

If using vinegar, circulate pure vinegar in system by running car for a minute or two. Then turn off an let sit for the period of time described. Then flush with a hose while engine running and radiator petcock open to vacate vinegar and crud.

Drain again at both petcocks, install thermostat and fill with distilled water only until water pump and timing belt are changed. After water pump and timing belt change fill with 50/50 antifreeze and distilled water.

Flushing Questions:

1. Should I use a commercial radiator flush to remove the rust and corrosion? If so what is a good brand and one that is safe for the system to use?

2. Should I use vinegar in the system instead of the radiator flush? I have read somewhere this is a safe and very good way to clean out the cooling system of rust and lime or other build up without damage to any seals or rubber components.

It was stated to leave it in for a 24 to 48 hour period and then flush with water.

3. Is it not necessary or recommended to flush the system with anything other than water to prevent any damage that could occur from the using flushing agents above?

Any comments or suggestions on this procedure?

Thanks to all in advance for your help.

Clark

 

Is there a particular problem you want to cure - ie oil contamination, rust removal, silicate drop out etc? Are you having heating/cooling issues or is this just preventative measure? Considering Volvo's have aluminum components, I'd choose a flush that is aluminum friendly. If you are doing this as routine maintenance, then you don't need to go a super aggressive route. If you have heating or cooling issues, then you may want to go a bit more. I'd also suggest you consider changing the engine's coolant temp sensor at this point in time while the system is drained (if its an original part) and install a new overflow cap as they do age as well. Commercial products should be fine - just choose based on your goal - ie Gunk's products got high marks for agressive flush with rust removal, with CRC and others marketing various flush mixes.

 

I doubt that there is any reason to get aggressive. I would only use distilled water. If you pull the thermostat and it looks spotless in there, the rest of the system is likely the same.