Carb rebuild... (1 Viewer)

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breckbone

breckbone

Joined
Apr 11, 2006
Threads
43
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303
Location
Burke, VA
Hi all. I think I'm headed down a path to rebuilding my Rochester carb that's in my '68 FJ40. I'm not sure where to get the rebuild kit, tho. I've seen links for rebuilt Rochesters and some rebuild kits, but not kits for a Rochester.
Also, in a couple days, I'm planning on flushing my fuel tank to diagnose a new problem. My engine is running roughly and is extremely difficult to start. I was told by the guys at Iron Pig that it could be either a fuel prob or a carb prob or both...hence my upcoming projects. Is flushing the tank as straight-forward as it seems? (remove tank, drain/rinse, reinstall, replace filter, refill, disconnect fuel line from carb, turn engine to pump fuel thru line until it looks clean, reattach) Any tricks/caveats I need to watch out for? Any advice would be appreciated.
Thanks!

Craig
 
Craig:

Not that I know squat yet about cruiser repair, but it may be worthwhile to just check the fuel filter first. If it's clogged up, replace it and keep driving. If the problems soon return, then you may need to start flushing.

If the fuel filter isn't clogged, you can start looking elsewhere.

My 2 cents.

- Dave

EDIT: If you decide you ultimately do need a new fuel tank, go OEM. DO NOT GET A POLY TANK!
 
That's probably a Rodchester 2G? Great carb, not as good as stock, but they can work decent. Better than a webber any day.

You can get a rebuilt kit for it at just about any auto parts store, hard part is to figure out what the hell it came off of. You can also buy them rebuilt at Autozone and on line. I'd chuck it and get a rebuilt one from a Guru like Mark's Offroad. Forget the locals, your wasting your time there, go straight to the carb experts like him or Jim C.

There is a great guy over in Alexandria that runs a radiator/gas tank shop. He did the gas tank on Jim's HJ45, my Porsche and several other friends of mine. I can dig up the number if your interested. Right off of Edsal and General Washington Dr.

When you flush out the tank, you can only do so much yourself. Really need to get it flushed in acid and then sealed. On my 356 and Jim's HJ45 it made a huge difference. I'd go ahead and just replace all the hard and soft lines. The hard line is easy to make and the soft lines are cheap. On the early FJ40's the fabric covered soft line is no longer available last I checked though.. In that case, blow out with compressed air and carb clean.

-Stumbaugh
 
Blue77FJ40 said:
Cool - a 356. You still have it?
Click to expand...

Thanks man, it was a neat old car. Just sold it about a month ago, sold my other one about 2 years ago. The 356 cult is amazing, there are guys like my wifes uncle who have owned the same one for 30, 40 or even 50 years now. He bought his Speedster for $3500 and now it's worth $100,000.00 or more.

-Stumbaugh
 
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The Rodchester is junk. I had one and scrapped it. The afflicted linkages are worse than the carb though. Go Back to an asin carb. Find a used one here and send it to JimC or Mark is your best bet.
 
wesintl said:
The Rodchester is junk. I had one and scrapped it. The afflicted linkages are worse than the carb though. Go Back to an asin carb. Find a used one here and send it to JimC or Mark is your best bet.
Click to expand...

I agree with everything you said except for the carb itself being junk. I had one recenlty on a 78 FJ40 and it ran VERY well. I also ran one in one powering a 225V6 on one of my Willy's back in the 1980's and it worked very well on that applicaction too. AND, I had one one on a 292 I6 that snorted like beast when you gave it the skinny pedal (like your red 75, it fooled many people into thinking it was a V8). It's a great carb on the right aplication with the right linkage, aircleaner, etc.

The carb is not junk, the POS manafre linkage and adapter is though...

However, I'd never argue that going back to stock is not better and the linkage was afflicted looking.

This subject will never seem to die, the stock Aisin carb is the de facto standard!

-Stumbaugh
 
Trust me, if I was rich enough to own a FIA Cobra with Weber IDA's (or any other Shelby with Weber’s) I'd be willing to brag about having them...

Same goes for the Ferrari 250 GT0 V12 with SIX Webers or any other of Enzo's cars. Hell, I'll take any vintage car with Webers.

There is nothing like the truely wicked, awe inspiring noise that comes out of that much induction and 7k RPM and triple banks of six stacks or 12 in the case of the GTO...it sounds so much nicer than a 4 barrel and makes so much more power. Webers were even banned from many FIA and SCCA races because the small block ford powered cars with webers were runing the same lap times as the big block cars.

Anything else, FAWK Weber.

A Weber on a F/2F is like a saddle on a pig or a football bat. Useless.

Now, Dellorto is the real deal when it comes to Italian made carburetion! Anyone who around in the days of old school motorcross knows that Dellorto is the s***.

-Stumbaugh
 
Thanks for the replies. Couple reasons I'm going rebuild first: I found a kit for about $10. If it doesn't work, not much lost. If it works "ok", then it'll hold me over 'til I rebound from all the work I just had done at the Iron Pig. Cam from the Pig recommended a Weber 38/38. I think I'm leaning towards an Aisin, though.

Regarding the Rochester 2brl that I have in it right now, it's my understanding that my FJ has a 2barrel manifold but came only w/a single barrel carb. Wouldn't going back to the stock single barrel be a reduction in power? This is an area I'm brand new to, so if that's a moronic question, I apologize.

As for the problems starting it, I think that it's more involved than just a carb/fuel problem. The old battery I had in there had a red indicator light. It was turning very very slowly when I was trying to start it. Sounded like a weak battery. My dad said that he'd serviced that old battery several times over the years and it was probably time for a new one. Got one today. Put it in. Same issue. VERY slow cranking. Now I'm thinking it's a wiring issue.
I put a call in to Lance and left a mesg explaining my problems. He (or Cam) just did a bunch of wiring for the lighting in my truck and I'm not sure if something else was adversely affected. They also replaced the shocks, shackles, bushings, clutch, and transmission...non of which, as Cam told me, should have any affect on how the engine runs.

So, until I can actually get the engine turning fast enough to start, I'll have to hold off of rebuilding the carb.

Thanks again for the info!

Craig
 
Slow cranking could be a bad ground. Check the battery cables, or better yet replace them with oversized units. Also put a ground strap from the motor to the frame and make sure the connections are shiney, clean steel when you bolt it back together.

Many times just a rebuild kit does not fix all the woes of a worn out carb, the shafts wear and cause vacuum leaks...

-Stumbaugh
 
Could a bad ground also affect how it drives? When I was driving back from Fredericksburg, it felt like I was driving into a strong headwind even though it was calm...

Driving it back down to the Pig tomorrow afternoon...assuming I can get it started.
 
Rebuilding a carb is really not an easy task. I think John is right on trusting experts. I tried my hand at it once.... It didn't work at all after all that work. but it was a good experience!
 
breckbone said:
Could a bad ground also affect how it drives? When I was driving back from Fredericksburg, it felt like I was driving into a strong headwind even though it was calm...

Driving it back down to the Pig tomorrow afternoon...assuming I can get it started.
Click to expand...

Why go all the way down there? Take it to Wisam in Vienna, AK Auto in Fairfax, Car Doctor in Falls Church, Japanese Auto Clinic in Falls Church, Chandler Bros in Sterling, High Tech in Chantilly, etc, etc. There are thousands of SAE certified places a stones throw from your house. That's a long drive and or an expensive tow if you break down on the way. Wherever you go, make sure its a SAE certified tech that is working on your car, shade tree turned pro is pretty scary. Better yet, just fix it yourself!

Some ideas:

Usually, when an old truck is running badly, it's a multifaceted problem. When one problem is more severe than another, it is made even worse by the smaller problem.

You may have a bad ground that is causing it to crank slowly, and I guess in theory this could cause the truck to have a weak ignition system. Have I seen that before first hand? No. You should pull off a plug wire and check for spark, is the spark blue or orange/yellow?

Blue=good, healthy system with good ground and coil/etc.

Yellow or orange means there is a problem somewhere.

You need to check all of the basics:

Compression? Preferably a leakdown test...

Vacuum test?

Fuel delivery? Clogged filter? Clogged tank pickup?

You need air, fuel and fire (spark) for the engine to run correctly.

-Stumbaugh
 
You can also use a jumper cable from the battery negative to the starter housing to check to see if there is a bad ground or cable. Just take a wire wheel/grinder/3m disc, etc to clean up a spot on the housing. MAKE SURE YOU DO THE NEGATIVE!:eek: This is a nifty trick for fixing all sorts of little hassles that are related to bad grounds. I have fixed a power windows this way. Quick way to figure out that it's just a bad ground.

Are you going through batteries? Is the alternator healty?

AND Napa has some nice beefy oversized battery cables for cheap, so does Tractor Supply.

This is why you replace all of the weak links in your truck.

Hoses

Battery and Cables

Belts

U joints

Filters

Spark Plugs

Plug Wires, Cap and Rotor. (Coil, resistor, ignitor, resistor)

Grease and Fluids.

No matter how mechanically inclinded you are you can replace these part and if you keep all of these parts in good shape you'll eliminate many little sources of trouble that can make the truck run bad and or leave you stranded.

All of these are cheaper than a single mechanics visit.

-Stumbaugh
 
Stumbaugh said:
Thanks man, it was a neat old car. Just sold it about a month ago, sold my other one about 2 years ago. The 356 cult is amazing, there are guys like my wifes uncle who have owned the same one for 30, 40 or even 50 years now. He bought his Speedster for $3500 and now it's worth $100,000.00 or more.

-Stumbaugh
Click to expand...

Wow, looks like a Cabriolet. I've always wanted a 356, but won't do that until I find/buy/get a garage. Back in the day, I "Herbied" my 1300 with porsche engine parts blowing away all comers until a 5th gear porsche took me. (Bug only has 4 speeds). I even autocrossed it for a while.

On my first 77 '40 I ran a Rochester 2bbl on a 283 V8 in it no problem. Ran great as a matter of fact. However, if I knew then what I know now, I woulda just done a head job an kept the 2F.
 
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Holy schnikeys! He ended up at about 150 mph!

If someone drove me in a bus at 150 mph, I think I'd have to change my pants.
 
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