88 b2200 stock rebuild and having idle issues

I just got the b2200 my parents purchased new in 1988. My sister has had it for some time and has neglected it. I recently did a complete rebuild on the engine. After getting it running I quickly discovered the muffler had collapsed and decided to put a new weber 32/36 on it. My issue is I can get it idling GREAT in the driveway but after I drive it for a little while it idles rough. I've gone through all of the instructions in the weber docs and it still does the same thing.

Just some BG info on the rebuild:
New distributor
New Wires
New plugs gapped to 32
New timing belt (timing is right)
New tensioner
new water pump
new fuel pump
new oil pump
new muffler

I've timed it with the light several times but it still idles rough. I pulled the vac advance hose off and put it at 6 degrees BTDC but it runs better around 10 degrees BTDC. Back in the day I used to just time my camaro and GTO by ear and never had problems (that I knew of). What did I know I was a teenage kid who thought he knew it all. HA!!! I adjusted the idle mixture screw this morning before work and thought I had it figgured out. Well when I got to work it was running like an old tractor...just shaking and idling rough.

Anyway...sorry for the novel. If anyone could shed a little light on the scene, I'd appreciatee it. I'll add...I've done my homework and have spent MANY hours looking at old posts. Some helped but im still in the same rough-idling boat.

Why, I find that so difficult to believe !!!!

Anyway, I also have a 1988 B2200 with 32/36 DGEV Weber with an engine I did in October. I re-used my Weber carb and adapter gaskets, and had vacuum leak there. Since I didn't have new gasket for there (would've needed to order from California or NY) I bought rubberized gasket material from O'Reillys and cut new gaskets to fit, and also used Permatex Aviation as sealer, and torqued everything correctly. Then my idle was as it had been before the rebuild (was smoking, why I built it).

The Weber carb is very prone to vacuum leaks, maybe the adapter plate isn't perfectly flat. And a vacuum leak there affects your timing, I had that as well. So once I re-did those Weber gaskets, then set timing (I'm using 6 BTDC), then purrs like a pussy.

I'm also assuming that your Weber choke heater is plugged into the rear of the alternator, like it should be.

Thanks for the reply...I'll check into the plates by spraying a bit of carb cleaner around them & see if I get a change in engine speed. The plates and gaskets were new and I used sealer on them when I installed. I normally wouldnt have used the sealer but all the posts I read here said to use it...so I did.

Yep...your asumption is correct...the choke heater is plugged into the back of the alternator & it's got juice to it.

There's a mechanic close to the house and I'm tempted to take it to him but I'm to stuborn. Maybe this thing will beat the pride out of me & I'll give in.

One thing I forgot to mention was that there is no thermostat in the engine. I took it out because after the rebuild I was worried the engine would overheat & I'd be buying a new head. The truck barely heats up when I drive it now but heats up in the driveway, as excpected. Could the lower temp be causing the crappy idle?

One thing I found today while jacking with the mazda was that I left off a vacuum cap on the intake manifold...so it was sucking air. I plugged it up with a rubber cap and the engine dern near died. I adjusted the fuel/air mixture and the idle again & it's somewhat better. The thing I keep having an issue with is the timing. It seems like it runs WAY better when it's out of time...like 12 - 14 degrees BTDC. I take the vac advance hose off, get the engine idling around 800Rpm's (or whatever the book says) then time it at 6 degrees BTDC and it runs worse. I took it for a test drive with it at 6 degrees and then again at 12-14 degrees and it has more power and runs better at 12 -14 BTDC. Looked at the marks on the timing belt and crank & they're dead on.

Oh...and I let it sit for a few days and tap, tap, tap...lifters making a horrible tapping noise. GRRRRRR.....sometimes I wish I would have let this thing go to the junk yard.

Help...I've fallen down on this rebuild & cant get up!

Sometimes a second pair of eyes can help.

Cusser,

Thanks for the reply...again.

I'll slap that thermostat in it this weekend.

How does one check the functionality of a fan clutch?

Jeff

From my saved "archives"

If you want to test your fan clutch, it is not even necessary to remove it. While the truck is cold, and turned off, spin the fan by hand. It should turn easily. Then when the engine is hot, turn off the engine and spin the fan by hand; it shouldn't spin very much, less than 1/2 turn or so, should have considerably more resistance than when cold, if it's good.

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If you want to test your fan clutch, it is not even necessary to remove it. While the car is cold, and turned off, try and turn the fan. It should turn easily. Then start warming up your car. As you stop the engine and test the fan, it should get progressively harder and harder to turn freely. It will never lock up completely, but you can tell that the clutch is working.
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The fan clutch is designed to be tight when hot air is passing by. When
enough cooler air is passing by, it disengages sort of, to reduce the load on the engine by letting the fan not spin at the same speed as the enging. The fan clutch engages to make the fan turn faster when the engine needs
extra cooling, like on hot days or when idling at a light on a hot day.

Good info, cusser. I'll take a look at it tonight. Based on your post and what i've seen with the fan clutch from working on the engine, I think it's shot.

Here in Arizona heat, they seem tolast 5 - 6 years. Mine's a Hayden that had a lifetime warranty, and I've swapped it out several times.

Not only can a bad fan clutch cause higher running temperatures, it can also cause AC vent temperatures to be higher, as the AC condenser doesn't get sufficient air flow.

Im poretty sure this is the same fan clutch that came with the truck in 1988. Surely it's a gonner!