When my VXR8 was at
MWP last Sep for a tune-up I was advised to replace the auxiliary belt tension as it wasn’t as smooth as it should be and belt slap was occurring. As I don’t drive it like a possessed maniac it wasn’t top of my list to sort.
Last month after popping it back on the road I was doing my usual poke and prod checks as you do and spotted a pink haze under the thermostat so cleaned it up and monitored and sure enough it had a slight weep with coolant as full temp/pressure, not enough to drip but it needed sorting.
Fast forward to a few weeks ago and after digging deep finding the cheapest UK suppliers for a genuine GM tensioner and thermostat it was still cheaper to buy from
RockAuto in America. The usual epic two-day delivery (import duties included) and these arrived.
LS2 6.0L auxiliary belt tensioner genuine GM part no.12569301
LS2 6.0L complete thermostat genuine GM part no.600172 / AC Delco part no.1511057
Fitting was relatively easy so I popped the auxiliary belt off and removed the tensioner.
With the tensioner off it gave better access to the thermostat so my coolant clip tool was deployed which makes removal a doddle as they are ratcheted and lock the clip open.
I carefully drained the coolant from the hose and stat and managed to drain 5.5L. There is a drain bung at the bottom of the rad but I simply couldn’t be bothered getting it in the air when I could drain it with minimal spillage from the state housing.
You can see where the stat seal has gone and coolant was weeping past. It was only a few pounds/dollars more to buy a complete stat unit instead of just the seal. My thoughts are with the age and mileage of the car why not replace the whole thermostat unit.
I cleaned the stat mating face and cleaned all threads using my thread cleaning taps which are exactly that and not for cutting new threads.
Popped my favourite goop on the seal, yes you can assemble dry but I prefer to add extra security/protection, then bolted it on torquing to 14Nm as per the workshop manual.
The tensioner was then bolted on torqued to 58Nm and auxiliary belt fitted with coolant hose attached. Left it like this for a day for the sealant to cure.
Next up was adding the coolant in slowly, running the car to burp the system and get the air out. Having not done this previously it took a while.
The coolant system in sealed with a pressurised radiator cap (black cap on right) and bleed hose from the cap area to an expansion tank (yellow cap on left). The coolant system when cold can be checked for level using the expansion cap level strip and should be at or above min mark when fully cold and at or below max when fully hot. It’ll push coolant out the pressurised system to the expansion tank when hot and suck it in when cooling down/cold so the expansion level will go up/down so can be checked hot or cold, simples got it good.