Hello everyone, I'm as new as them come.

Just purchased a beautiful 1987 Toyota Pickup 4x4 XtraCab DLX and had her shipped from Colorado where she'd been sitting in a garage for the last several (unknown) years. Only 121,000 on the truck, but she still ran like ˟˟˟˟, spat fuel, and had numerous vacuum leaks.

I replaced the fuel air system (new fuel pump, running to fuel pressure regulator [holding 3psi], running to a Weber 32/36 from Redline). Also installed new distributor, plug wires and plugs. The engine runs great, HOWEVER, exhibits the following symptoms:

1. Diesels after I shut her off (yes, I know, I should install an idle shutoff in the Weber but I'd rather fix the problem [idle mixture probably] than alleviate the symptom.

2. She dribbles quite a bit out of the exhaust after starting up.

3. Idles fairly high WITHOUT the idle screw even contacting the throttle.

4. The (not sure what to call it) front cover gasket, as well as the head gasket are a little juicy, and look like they have been for some time.

5. And lastly, despite proper properly installing the Redline Weber adapter plate sandwich multiple times, (seems like a stupid design, especially being cast and not machined) I believe I've got a slight vacuum leak around the base of the carb (if I dribble starter fluid the idle picks up)

I really want to take care of this truck, I'm going to MPG not so much HP, and I'm more than willing to do what's necessary to get her running tip top.

Suggestions/advice on any one or all of these issues would be greatly appreciated.

Thanks all!
-Jackson

 

This is likely going to turn into a short novel so grab a beer, cup of coffee or whatever you need to get through it...

1 - Dieseling isn't necessarily caused by the absence of a fuel shut off solenoid. I run a Weber 38 and used to run a Weber 32/36 (both without a fuel shut off solenoid) on my 22R and it NEVER diesels. Dieseling can be caused by hot spots in the combustion chamber caused by lean conditions or carbon build up, vaporized fuel in the crank case, incorrect timing, high idle speed, high float level, leaking carb, etc. Tuning is likely to blame, so I'll address that later on in this post. If you have a manual choke Weber then a fuel cut off solenoid cannot be installed (for some reason the carb bodies are slightly different and the solenoid doesn't fit). If you have an electric choke and you still want one let me know; I have a brand new one somewhere in the garage that you can have.

2 - What "dribbles" out of the exhaust? Fuel, oil, condensation? If it is fuel, we need to get that Weber tuned properly AND you need to check your spark plugs and possibly the valve seating. If it is oil, you've got some blow by and your engine is like nearing the end of its efficient life. If it is condensation, then you are likely in the clear - hot exhaust running through a cold exhaust will create condensation plus water vapor is a by product of combustion, but if it is coolant...a head gasket job is in your eminent future.

3 - Go back through the tuning procedure. Where are you located? Webers are jetted to a sea level environment. If you are at a high elevation then you may need to go with smaller jets.

4 - If you are getting oil leaks around the timing cover gasket, you can try to buy yourself some time by re-torquing the bolts on the timing cover. All 8mm bolts (12mm socket) get torqued to 8-11 ft-lbs and all 10mm bolts (14mm socket) get torqued to 26-36 ft-lbs. You'll want to remove the bolts completely, clean the threads with a wire brush as well as you can and re-installed them to get a more accurate torque on them. Do each bolt one by one so you don't completely break the seal on the gaskets. This may solve your problem for now, but you may eventually want to replace the timing cover gaskets, which would be a good time to do the timing chain as well. If you decided to re-torque the head bolts, I would highly recommend buying new bolts. Head bolts are torqued to 53-63 ft-lbs. You want to torque from the center bolts and work out, alternating sides. Here's the pattern:
-1: Intake side between #2 and #3
-2: Exhaust side between #2 and #3
-3: Intake side between #3 and #4
-4: Exhaust side between #1 and #2
-5: Exhaust side between #3 and #4
-6: Intake side between #1 and #2
-7: Exhaust side between #4 and firewall
-8: Intake side between #1 and radiator
-9: Intake side between #4 and firewall
-10: Exhaust side between #1 and radiator
Again, this is just buying you time, the head gasket may need to be replaced soon.

5 - Here's what you do. Gently remove the Weber adapter, walk it across the garage, throw it as hard as possible into a trash can and to be sure that it never plagues another soul, douse said trash can with lighter fluid and torch it. Weber adapters simply SUCK! Anybody who tells you otherwise either has REALLY good luck or is satisfied with vacuum leaks. I can't speak for the transdapt adapters, but do yourself a favor and get a LCE spiral adapter. I use one on my 22R and it works great! No leaks and even gives you a couple extra horses. I actually used it with my Weber 32/36 and re-used the gaskets when I went to my Weber 38 and still didn't have any leaks. Here's the link, get you one:
http://www.lceperformance.com/Spiral...-p/1033060.htm

Ok, so now you need to get that Weber running right. Before you go pulling off that crappy Weber adapter and replace it with a LCE adapter, get it running as best as possible so that you can set your timing as close as possible to where it needs to be. This will help minimize at least one variable when you go to tune the Weber. Per Toyota's specs, the timing should be set at 5* BTDC with the vacuum advance cut or pinched off at idle speed (950 RPM max). HOWEVER, I have found that 5* is not quite enough advance so I typically start at 8* BTDC with the vacuum advance pinched off at an idle speed around 800 RPM. While you're at it, set your fuel pressure as well. Weber says 3.5 PSI max, but I have found that 2.5 PSI is usually ideal for me.

Now that you have your timing and fuel pressure set close to where they need to be (small adjustments may need to be made later, but not much), go ahead and can that Weber adapter and install the LCE adapter. While you have your carb off, its not a bad idea to check your float levels. They are typically ok when they come from Weber, but that isn't always the case. I had to adjust the float on my 38 by about 4mm when I got it. If you don't know how to do it or need the specs, just ask.

Now install the carb and set your baseline settings per Weber's best lean idle method. Since you have your timing and fuel pressure close, then this method will yield good results. Baseline settings:
1-The idle speed screw should be initially set at 1.5 turns in. You need to turn the screw out until it doesn't contact the idle speed linkage arm then turn the screw in 1.5 turns AFTER initial contact with the linkage arm.
2-Idle mixture screw should be 2 turns from bottoming out. You need to turn the screw all the way in until is stops (Just snug - don't go cranking down tight on it or you'll jack up the seat) then back the screw out 2 full turns.

MAKE SURE THE CHOKE IS COMPLETELY DISENGAGED! Manual chokes are easy to be sure that they are off, but the electric choke can be a pain in the ass. I would just completely remove it and re-install it later if you are unsure. Just make sure that the fast idle screw for the choke is not engage with the lever - this could have been the cause of your fast idle issue.

With your baseline set, fire her up. It should start up fine but run a little rough. DO NOT ADJUST THE IDLE SPEED SCREW. Turn your mixture screw in until it nearly dies, then turn it out until it nearly dies (be sure to count your turns). After you find out where it almost dies in both directions, then find the middle between the two and that should be ABOUT where you need to be. Keep in mind that it won't run absolutely perfect, but you looking for the best idle that you can achieve at this time.

Once you get the idle mixture set, now you can adjust the idle speed. You should be setting your idle speed between 700-900 RPM. How fast is preference, but I like to be around 780-800 RPM. It should be close to begin with if the jetting is correct.

From here, I like to verify my timing. I double check that I am still set around 8* BTDC with the vacuum advance pinched off. If that checks out then I go through the whole Weber tuning again to get a better tune on the carb. Find the near stall position in both directions of the mixture screw and find the middle of the two. Then go back and verify your idle speed is set to where you want.

Now you should be really close to where you want to be HOWEVER, you need to check a couple things. Verify that your mixture screw is between 1.5 and 2.5 turns from bottoming out (I like to mark my mixture screw and a reference point on the carb body with a sharpie). If it is under 1.5 turns out then the jet is too rich and you will need a smaller idle jet. If it is over 2.5 turns out then the jet is too lean and you will need a larger idle jet. If the engine is healthy and relatively stock, elevation is typically the main factor in needing to re-jet. If the idle speed screw has to be turned in more that two turns (3.5 turns in from initial contact) then you have a lean condition which will likely require a more extensive re-jetting scenario - that can be a bit of a pain if you aren't a carb savvy guy.

Set up your choke last. Personally, I prefer a manual choke because I try to rely on electronics a little as possible. Plus I hate having to wait for an electronic or water choke to close and my truck NEVER needs to be choked to start. I drive my truck to work this morning and it fired right up in 40* weather after sitting for at least a week.

If everything checks out, go for a little test drive. You may notice a slight lag when you getting into the secondary barrel, but that can be minimized later - you likely won't be able to get rid of it complete because it is typically caused by the accelerator pump's initial insufficiency when tapping into the secondary barrel. Ideally, you're looking for a nice constant pull as you accelerate. After a test drive, you're simply looking at fine tuning or a trial and error scenario to get it to run as best as possible for your driving environment. Here's what I like to do after about a 30-45 test drive:

1-Pull the spark plugs. Ideally, you want to start this endeavor with new plugs so that they are more telling for trouble shooting. You're looking more at the ceramic portion of the plug here. If the plugs are are slightly brown (like cappuccino colored) then you are likely running lean (too little fuel) which will cause the combustion chamber to run hot thus "toasting" the spark plugs. If they are almost black and covered with soot (if you have oil consumption issues then make sure you aren't mistaking burnt oil for soot - burnt oil will be wet, soot is dry) then you are running rich (too much fuel). Ideally you want the plugs to come out as white as possible. It's a good idea to have a few new spark plugs on hand to replace at least one each time to do this test so that your results are accurate when you pull the plug on the next evaluation. This will give you an idea of what the AFR is so that you can adjust the mixture accordingly.

2-Weber says to tune the carb by ear, but that doesn't get a fine enough tune for me. I have a digital timing light with an RPM reading so I hook it up and adjust the mixture a little at a time in each direction until I get the highest, most steady RPM possible. After each small adjustment (I'm talking less that a 1/16th of a turn here), I snap the throttle a couple times to ensure my readings are accurate and repeatable. I'm also looking to make sure that the engine doesn't stumble when I snap the throttle.

3-I then fine tune the timing. With the digital RPM timing light, I advance or retard the timing slightly until I get the highest, most steady idle. This time, I adjust the timing WITH the vacuum advance hooked up and I'm not looking for a specific timing setting, just where it runs best.

4-Double check that the idles speed is still set at 780-800 RPM

5-Repeat #2

6-Repeat #3

7-Repeat #4

8-Go for a nice long test drive (like 50+ miles) or just drive it regularly for a week or so and note any performance issues. Test drive the way you plan on driving it. If you plan on wheeling it, go wheeling. If you plan on daily driving it, daily drive it. Tuning for each of those scenarios is slightly different.

9-Check the plugs again

10-Rinse and repeat if desired...

There is one more check to see if you have your timing set to where it should be. Have the truck warmed up and shut it down. Assuming that you have good spark, a strong starter and a fully charged GOOD battery, when you start it back up, it should fire up with not much more than a bump of the ignition. If it turns a few times then fires or if hard starts then you could be looking at a timing issue. It should literally bump and go "VROOM" but if seems like it is turning slow or is struggling to make that first turn and then fires (Kind of like you have a dying battery, but you know you don't I'll try to type the sound..... "VrrrrrROOM!") then suggest you take a look at your timing.

In using the method above, I have never had any major issues outside of VERY FINE tuning. The key is to repeat the steps over and over to get the tuning better each time. Typically, going through the steps once is fine for most people, but I am somewhat a perfectionist so I want to get it exactly on. This is the best way to achieve a good tune without an AFR meter. Assuming that you have the appropriate jets for your driving conditions and engine then you should yield desirable performance.

Good luck and let me know if you have anymore issues! Always willing to help!

Again, sorry for the book here...