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hard starting when motor gets warmed up

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tomj View Drop Down
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Post Options Post Options   Thanks (1) Thanks(1)   Quote tomj Quote  Post ReplyReply Direct Link To This Post Posted: Aug/08/2018 at 11:24pm
a cheap test to see if it's carb heat soak is easy -- if you know the time window where it's hard to start, when you park the car leave the hood open. that'll let it cool much faster.

if that fixes/reduces the problem, there you go. if not...

1961 roadster american
195.6 OHV, modded
T5z, 3.42:1 mustang axle
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Thikstik Quote  Post ReplyReply Direct Link To This Post Posted: Aug/09/2018 at 8:58am
Ha COOL!  I got pics of her in my fone as we speak.  I didnt ever find the Wisconsin crew with the sportabout and Hornet 360.  Congrats man.
75 gremlin x, jeep 4L headed 258,Clifford cam, intake,header. 390 holley. I want a 282 VAM motor!

AC/PS/PDB.

72 AMX , 304 2bbl, 3speed, now disks...probably will sell, want an automatic /AC.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Thikstik Quote  Post ReplyReply Direct Link To This Post Posted: Aug/09/2018 at 9:27am
Can you say what mileage you got?  I cant recall T-5's overdrive.
75 gremlin x, jeep 4L headed 258,Clifford cam, intake,header. 390 holley. I want a 282 VAM motor!

AC/PS/PDB.

72 AMX , 304 2bbl, 3speed, now disks...probably will sell, want an automatic /AC.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote 73Gremlin401 Quote  Post ReplyReply Direct Link To This Post Posted: Aug/09/2018 at 9:35am
The other thing that causes hot-start issues in the summertime is ethanol-blended fuels.  Our cars were not designed with that in mind, and these fuels percolate more easily, causing vapor issues.  I've found that just making sure that I only put fuel in my carburetor equipped cars with non-ethanol blended fuels completely solves the problem.

to find places that sell non-blended fuel, I use the 'pure gas' app on my phone.  Works great, especially when traveling.
73 Gremlin 401/5-spd.
77 Matador 360/727.
80 Concord Limited 4dr. 258/904


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Post Options Post Options   Thanks (0) Thanks(0)   Quote 71 Javelin AMX O.O. Quote  Post ReplyReply Direct Link To This Post Posted: Aug/09/2018 at 12:39pm
not a hot start problem, but thought I would ask anyway to keep this tread going on carbuators..
I recently had a heater hose give way and blew antifreeze all over the engine compartment.  I cleaned up all that was visable and noticed that some antifreeze actually got into the air filter housing.  Cleaned that up.  Then I noticed that when cold started I had to give it gas to get it to idle.  No fast idle.  So I opened the choke cover and sure enough there was antifreeze inside the housing.  I cleaned everything with carb cleaner, and it started up like it did before the hose break.  I'm hoping I got the carb outside and inside cleaned up.  I'm guessing the sticky antifreeze was screwing up the linkages and choke spring. 
Anything else I should be looking for that may give me problems, in the future?  I took the PVC valve out and blew carb cleaner through that and it rattled like it's suppose.  Cleaned out the carb vacumn lines, too.
Steve
1971 Javelin AMX
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Post Options Post Options   Thanks (0) Thanks(0)   Quote tomj Quote  Post ReplyReply Direct Link To This Post Posted: Aug/10/2018 at 1:00am
Originally posted by Thikstik Thikstik wrote:

Can you say what mileage you got?  I cant recall T-5's overdrive.


i got 22.7 MPG over the 6500 mile drive! i'm happy with that.  i got the close-ratio T5 from Modern Drivelines. rare for me to buy such a fancy part! totally worth it. 

5th is 0.73, axle is 3.43:1, tires are 24". i drove 65 to 75, 2300 to 2600 rpm.

1961 roadster american
195.6 OHV, modded
T5z, 3.42:1 mustang axle
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Post Options Post Options   Thanks (0) Thanks(0)   Quote vinny Quote  Post ReplyReply Direct Link To This Post Posted: Aug/10/2018 at 1:53pm
That is still better by 1 or 2 MPG than an 07 Volvo XC90 with an equivalent sized engine. My 64 Classic with a 232 gets about the same as the Volvo. I have a feeling that with frequent starts when hot the Rambler mileage would be worse.
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Post Options Post Options   Thanks (1) Thanks(1)   Quote tomj Quote  Post ReplyReply Direct Link To This Post Posted: Aug/13/2018 at 1:10am
i generally run the cheapest gas i can find, nearly always with ethanol, and have zero troubles. all hoses are new, so no hose issues.  tank is clean, that helps. on the power tour i ran midgrade, as a sort of magic talisman to ward off pinging (probably a waste of money). not had fuel related problems in many years. compression was raised to 9:1 too. lots of spark timing.

i'm sorry to be argumentative, but all our carb cars are instant start, or two, three seconds cranking after they've sat long enough for fuel to dissipate, multiple days, (is what i assume is happening). hot start, cool start (we don't get cold here), no matter.

carbs require a lot of attention, relative to FI. and its true, as carbs wear and get old they get weird and hard to tune -- the metal wears, surface finishes degrade and emulsions and surface films on old carbs don't work as well as new carbs. sometimes rebuilts are just fine, sometimes they never work out. junk unrebuildable carbs need to be thrown out.

personally, YMMV, etc, i just gave up on old carbs, the castings themselves mysteriously deteriorate. i buy new carbs only. they last "forever" (i did sell my 4, 5 year old Weber 32/36 to buy a Weber 38/38, and i might replace it with the larger IDF 44). that's work and not appropriate for all cars.

my only point is start issues are not simply life with a carb. carbs work great, but they have to be kept in top notch shape, from tank to hose to pump to casting to spark timing.

we have a '72 Hornet with a 258 and a rebuilt Carter YF on it that's now 6? 8? 10? years old. it starts with one flap of the pedal and crank for under 1 second, on fast idle, drive off.


Edited by tomj - Aug/13/2018 at 1:13am
1961 roadster american
195.6 OHV, modded
T5z, 3.42:1 mustang axle
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Thikstik Quote  Post ReplyReply Direct Link To This Post Posted: Aug/15/2018 at 12:16pm
Originally posted by tomj tomj wrote:

Originally posted by Thikstik Thikstik wrote:

Can you say what mileage you got?  I cant recall T-5's overdrive.


i got 22.7 MPG over the 6500 mile drive! i'm happy with that.  i got the close-ratio T5 from Modern Drivelines. rare for me to buy such a fancy part! totally worth it. 

5th is 0.73, axle is 3.43:1, tires are 24". i drove 65 to 75, 2300 to 2600 rpm.

Thats about as good as it gets...great combo.  I always say that my Gremmy would be such a nice long range car if it had one more gear. Of course, same is true for any 1:1 old car. Is your engine aluminum or iron?
75 gremlin x, jeep 4L headed 258,Clifford cam, intake,header. 390 holley. I want a 282 VAM motor!

AC/PS/PDB.

72 AMX , 304 2bbl, 3speed, now disks...probably will sell, want an automatic /AC.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Trader Quote  Post ReplyReply Direct Link To This Post Posted: Aug/15/2018 at 10:38pm
RJ,
Found and fixed the problem yet?
The thread is going sideways.
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