RV8 top hose inserts
Anyone who has done the job will know what a pain it is to refill the RV8 cooling system when changing the coolant, or following work on the system. With the original RV8 cooling system, filling has to be done very slowly and, in the final stages, you are as likely to fill the valley gasket as the cooling system, when trapped air coughs back through the filler pipe. No amount of squeezing of the top radiator hose will fully purge air locks from the system, and entrapped air will accumulate in the arch of the hose when the engine is running - leading to reduced coolant flow and possible engine overheating.

Stuart sets out a detailed twelve point procedure for fitting the top hose self-purging insert and then filling the cooling system. He concedes it still appears fairly involved when written down step by step, but it is quite quick and easy to carry out in practice. It normally takes 3 or 4 minutes to fill the system from empty, rather than the 30 - 40 which has been quoted for the standard arrangement.

Although his car is fitted with a non-standard brass expansion tank, this top hose insert arrangement should work equally well with the standard expansion tank, or the modern replacement tank available from Clive Wheatley. Stuart is planning to make a batch of the self-purging inserts which should be available shortly through Clive at MGV8parts.

RV8 bleed insert in the top hose
In 2015 Stuart McGuigan produced a bleed insert to help remove trapped air when refilling or maintaining the RV8 cooling system. In RV8NOTE409 released in November 2015 Stuart set out a detailed twelve point procedure for fitting the top hose bleed insert.
See full copy of RV8NOTE409

RV8 self purging top hose insert
Now Stuart McGuigan has devised an improved solution in the form of a self-purging top hose insert fitted in the top radiator hose. A prototype fitted to his car is performing well. The detailed twelve point procedure is set out in a detailed article.
See a full copy of RV8NOTE434

Posted: 170301
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