Strange problem

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UK ,Bournemouth
I have a Horman HT1, If I run it with the body shell on after about 10mins the engine cuts out and the primer bulb on the top of the carb is empty. If I take the shell off The car runs perfect and the bulb stays full. I haven't cut out any of the windows so as not to spoil the shell, could my problem be engine overheating, Any thoughts welcome.
i would say Vapor lock, not overheating.

its getting hot enough under the lid to cause a vaccume in the gastank, thus a vapor lock, no lid, keeps cool enough so no vapor lock.
check your vent hole in your gascap, to be sure its venting properly or the lid isnt somehow covering the gas tank lids vent hole.
my experience with heat soaking is bogging after 10 to 15 mintues at med & higher rpms. but not sucking the fuel out of the carb and primer bulb. not to say that is not the issue here, but the fuel being sucked out of the carb doesn't strike me as an effect of heatsoaking or overheating, as much as a vapor lock issue.

On the HT1 there are 2 large dia pipes coming out of the fuel tank and finnishing at the back of the car so the tank has all the venting it needs without using a vented cap
ok then its not vapor locking. lol. my brave have fill/vent tubes but my baja doesn't. most i see don't unless the owner is a track racer.

then i ll have to agree with Marder beat and its heatsoaking. richen up the H needle 1/8 or so and you should be better.
Thanks Marder69 I didn't want to spoil the shell but it looks like holes in the screen is my only option. By the way whats the engine plate you mentioned, what is it and where does it fit and most important do they work?
Think he means one of these - I am waiting for one to come (about £6), but in my case it's to stop grass clogging up the fins rather than a problem with radiant heat.:)

Just realised the piccy is very small - anyway the FG part number is 7333 - here's a link to the page


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