Hi advice please, have a Marlin roadster with 1.6 pinto fitted, just replaced the old antifreeze, not a easy job as hard to get to rad filler so want to fit a filler neck in the top hose to top up easy, do I fit a plain cap to this or a 1.1 as is on the rad, thanks for help.

Is the hose at the highest point in the cooling system? Do you have an overflow connection on the rad neck ? If you do it maybe possible to block it off and use a flat sealing cap then use a pressure cap on the new filler. A possible better solution is fit a header tank with a bleed off hose and a Sierra type thermostat housing

Plain cap will be fine. If the current set up is good

The system works ok just hard to fill, Don't have room for a header tank, Both the rad has a overflow connection and the new filler neck, do I put both overflows into one? or block off on new filler, what I did forget to ask there is a outlet on top of the thermostat housing is that for a header tank? thanks .

[Edited on 23/11/19 by YOUSAY54]

The blank cap will not have an overflow.. so the system should be the same as before but just with a new filler point..

Thanks guys for the info on the way to sorting, thanks,