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rossjfox
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Hello all!  I recently purchased JH 20340!  Overall, a lot of restoration has been done, and considering  I drove it home 550 miles without difficulty, i have no complaints!

My question involves the idle.  It has strombergs, and with timing set at 8-10 BTDC, i can comfortably adjust the idle to btw 800 - 1000.  But then, once out on the road, the idle will slowly climb to 1200 - 1300.  Mostly annoying & with the cost of fuel, not appreciated!

Any ideas?  I was thinking a vacuum issue, possibly with higher operating temps once out on the road? 

Any help trouble shooting would be a help.

Thanks in advance.

Ross

edward_davis
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Ross,

The CD carbs have a bi-metallic spring inside them to adjust the richness with temperature.  Many people have disabled this bit, but if the spring gets out of adjustment, it can cause problems.  Also, I have noticed that just letting my JH warm up by idling doesn't get the carbs hot enough to activate the spring.  Adjusting the idle (or the richness) then won't get you to the right place when the car is running on the highway. 

My solution was to just re-adjust the idle on the road after I got the car going.  That seems to have worked pretty well.

The other solution is to pick routes with as little idling as possible....  =)

Welcome to the club! (Where are you located?)

Edward Davis

dwalls1
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Really appreciate this post and the response, as I'm having some problems adjusting the idle on 17798. Will try again after a good warm up. While I'm at it, can anyone help me out with how much oil to put in the Strombergs dash pots? The book says to "fill" them. Does this mean pour it in 'til it runs out? Thanks again. Dale

Jensen Healey
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The dashpots help to richen the mixture during acceleration. Fill with 20-50 to about 1/2" from the top. It's not critical if they overflow, just mop up.

rossjfox
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Ed,

Thanks for the advice!  I'll try to adjust with the engine full hot.

Regarding the bi-metallic spring, how would you disable this?  I know it's the long device on the side of the carbs; I can't imagine that you can just remove it.

BTW, I'm located in Denville, NJ.  Not far from Morristown.

Ross

Last edited on 06-09-2008 01:34 am by rossjfox

Jensen Healey
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Remove the cover and flip the flat metal spring over.

rossjfox
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Thanks!  I'll keep you updated.

Ross



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