8N won't start hot

[John Diercks]

1952 front mount, 6v, pos ground. Starts immediately when cold; runs fine. Will not start when hot/warm. Fuel out carb bowl is OK; spark checks out. What to check next?

 

[Bruce(VA)]

" spark checks out. "

Does it jump a 1/4" gap?

Do you use any choke when trying to start it hot?
50 Tips

 

[John Diercks]

Starts cold w/o choke; have tried with and without hot; does not even try to start. spark appears to jump 1/4" gap.

 

[GB in MT.]

(quoted from post at 16:57:53 04/06/12) Starts cold w/o choke; have tried with and without hot; does not even try to start. spark appears to jump 1/4" gap.

b:42128348e3][i:42128348e3]
John;
If that is the case with the spark, and you say, it runs fine....then, I suspect the air to fuel ratio, is out of adjustment.providing you have good compression on all four cyl's.
Try setting up the adj screws on the carb, like this...:

Gary [/i:42128348e3][/b:42128348e3]

 

[JMOR]

(quoted from post at 17:27:57 04/06/12) 1952 front mount, 6v, pos ground. Starts immediately when cold; runs fine. Will not start when hot/warm. Fuel out carb bowl is OK; spark checks out. What to check next?

ompression test is in order. Cold oil seals rings better than hot oil.

 

[DollarBill]

Starts cold w/o choke

That's a rarity - must be really fat. Most everyone has to use some choke.

Keep us posted - I'm curious to know your resolution.

 

[NoNewParts]

Does it turn over at the same speed when hot?
(hot starter failing, engine clearances too tight when hot)

If it turns over just as fast hot
some more ideas

mixture much too rich, should need choke to start cold, plugs fouling
when trying to start hot with 6volt slow turning

coil, ignition switch, ballast resistor failing when hot, all equal weak spark.

worn engine, low compression when hot

worn engine, oil thinning hot and fouling plugs

216 plugs, try 437's
(cold range plugs and some non-Autolite plugs foul easy in the presence of oil)

valve lash too tight. when hot, valves not sealing

some worn starters draw more amps when hot,
leaving 'not enough' left for the ignition circuit

timing off (too much initial timing-advanced makes
hard hot starting. probably not your problem with a front mount)

intake circuit leak that gets worse when hot