1975 2F Piggy with Weber 38 carb and DUI dizzy...need some insight please:)
- Thread starter jdog35
- Start date
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when cold it will be closed ...when the truck starts it will begin to open...it should be open fully pretty soon...functions off a bi-metalic spring
do you have 12v 'key on' sorce going to the elec choke?
do you have 12v 'key on' sorce going to the elec choke?
covering the bases
Others have mentioned it but you may or may not have a carb prob
at this point if I were in your shoes I would go back and cover all the basics with some quick and dirty checks. Once went through something similar and in the end I pulled the head and found anti freeze in the bore (67 spitfire)!
So check spark, and check plugs actually spark
check plug wires in the right order
you already did timing but check the rotor pos carefully---if I remember correct the rotor points to the #4 spark plug just before the no 1 plug post
Check the distrib is not 180 degrees out
do a compression check and follow on with a leak down test if you find anything there
check that it is not a choke problem by putting your hand over the carb and finness the amount of air you let in and try this while slowly accelerating
Try pouring a little gas in the carb while slowly accelerating and see if it seems to do any better
any suspected ignition prob run a jumper wire straight to the pos side of the coil
and last but not least not knowing whats been done make sure valve timing is correct as well as ignition
pull the plugs and look at them (google spark plug reading or color chart) are they wet? black and sooty? oily? tan?
The engine can bog too lean as well as too rich so when you open the throttle plate it dies (fuel/air mixture as with a vacuum leak or choke not working while engine is cold)
make sure the choke is open a little or open it all the way and just use your hand (watch for backfires)
check and double check for vacuum leaks
It may not seem like it could be that easy just doing quick and dirty checks but all of these have worked for me at some time or at least put me into the right system in order to start some serious troubleshooting
if the carb is truly bad for sure and I either didnt know how or didnt have time I would buy the orig carb and send it to fj40jim and have him rebuild it--it will be right when you bolt it on for sure
You are right to be cautious with mechanics, you know the drill---they will do the checks and then start changing parts and emptying your wallet---"Oh really? so the starter, battery, voltage regulator, and alternator all went bad at the same time?----and you replaced that wire?"
Best of Luck with it and hang in there, it can get bad but then again you are learning so much that will help you some time or the other right?
Others have mentioned it but you may or may not have a carb prob
at this point if I were in your shoes I would go back and cover all the basics with some quick and dirty checks. Once went through something similar and in the end I pulled the head and found anti freeze in the bore (67 spitfire)!
So check spark, and check plugs actually spark
check plug wires in the right order
you already did timing but check the rotor pos carefully---if I remember correct the rotor points to the #4 spark plug just before the no 1 plug post
Check the distrib is not 180 degrees out
do a compression check and follow on with a leak down test if you find anything there
check that it is not a choke problem by putting your hand over the carb and finness the amount of air you let in and try this while slowly accelerating
Try pouring a little gas in the carb while slowly accelerating and see if it seems to do any better
any suspected ignition prob run a jumper wire straight to the pos side of the coil
and last but not least not knowing whats been done make sure valve timing is correct as well as ignition
pull the plugs and look at them (google spark plug reading or color chart) are they wet? black and sooty? oily? tan?
The engine can bog too lean as well as too rich so when you open the throttle plate it dies (fuel/air mixture as with a vacuum leak or choke not working while engine is cold)
make sure the choke is open a little or open it all the way and just use your hand (watch for backfires)
check and double check for vacuum leaks
It may not seem like it could be that easy just doing quick and dirty checks but all of these have worked for me at some time or at least put me into the right system in order to start some serious troubleshooting
if the carb is truly bad for sure and I either didnt know how or didnt have time I would buy the orig carb and send it to fj40jim and have him rebuild it--it will be right when you bolt it on for sure
You are right to be cautious with mechanics, you know the drill---they will do the checks and then start changing parts and emptying your wallet---"Oh really? so the starter, battery, voltage regulator, and alternator all went bad at the same time?----and you replaced that wire?"
Best of Luck with it and hang in there, it can get bad but then again you are learning so much that will help you some time or the other right?
- Thread starter
- #124
Ill check that and confirm. I'm also thinking I should start over from ground-zero with the distributor and compression. I did that before, but didn't have anyone smart like you guys to bounce it off of to check for operator (i.e. ME!) error.
Rsb is going to swing by most likely tomorrow with a compression gauge and we'll check the valves too. At least this way I'll have a second set of eyes to check my work and report back to you guys.
I swear once this is done I'm taking all my notes and photos and doing a how-to so I never need to look at drawings or. search for actual pictures again
Rsb is going to swing by most likely tomorrow with a compression gauge and we'll check the valves too. At least this way I'll have a second set of eyes to check my work and report back to you guys.
I swear once this is done I'm taking all my notes and photos and doing a how-to so I never need to look at drawings or. search for actual pictures again
A fighter
that's right---taken a few good punches but he's still standin!
good idea to get some help and a second set of eyes, many many times ive tried to make things overly complicated for myself and then kicked myself later
like trying to balance twin su carbs when I had a cracked block doh!
that's right---taken a few good punches but he's still standin!
good idea to get some help and a second set of eyes, many many times ive tried to make things overly complicated for myself and then kicked myself later
like trying to balance twin su carbs when I had a cracked block doh!
He's in a valley and shouldn't be to much higher than sea level. Yeah, I guess sometimes you may have to make slight adjusments. I did, but only to the idle speed. Just seemed like alot of adjusments were made on his carb and still has the same problem. Hang in there Jake. You're close.unfortunitly not always true with the weber...its very often way too rich...and jetted wrong for the altitude
I have memories of doing the same with my triumph...a PITA ...and thats with a rebuilt engine...i can see having a cracked block would make it much harder
they were in a pepetual need of adjustment here in the upper north east as my DD...i switched to a weber....ahhhh....never touched it again
This is starting to become a real quest for rpm's if I can put it like that. I wonder did any of you think about disconnecting and plug off all vaccuum leads not neccesary to run the engine. Just to eliminate all vacuum leaks from external sources. I have seen brake boosters do strange things when not used for a while.
Good luck with finding the answers.
Good luck with finding the answers.
Where are you located? I'm in L.A. If you're not too far away, I'd be happy to stop by and check it out. I have some experience with that carb/dizzy.
Also, what about the quality of the fuel? If it's ancient or contaminated, that could contribute.
- Thread starter
- #132
Thanks guys. Fuel is new. I pulled the tank and did a full flush in August and made sure those lines were clear before reinstalling and refueling.
Going to tackle the compression, dizzy rotation, and valves this morning/afternoon with rsb. I'll report back live in an hour or so.
Thanks y'all!
Going to tackle the compression, dizzy rotation, and valves this morning/afternoon with rsb. I'll report back live in an hour or so.
Thanks y'all!
Interesting. I've rarely heard of an engine with the exact same compression in all cylinders. Whatever. You know what I would do now? I'd put a known good dizzy in and see if that works. Then I'd put on a known good carb and see if that works.
You've got two exotic unknowns on your engine and I would just eliminate one or the other as the possible problem.