Ka-BANG!

[datsunaholic]

Well, if anyone was trying to nap in my Neighborhood around 4PM they got one heck of a rude wake-up call, eminating from my 4X4.

 

For the last couple weeks my 4X4 has been giving me a hell of a time starting. Ever since it got cold and rainy... it did it a little last Spring, but I got through the summer just fine. Now it's pouring, and it won't start worth a damn.

 

I managed to get it started right before Jason came down from Canada to get some parts, but it took over an hour to GET it started, plus recharging the battery. It would spit and cough but once I let off the starter it wouldn't stay running. If I gave it no throttle, it wouldn't even make a pip. Same with lots of throttle. Half throttle it'd act like it wanted to fire... on one cylinder.

 

Pulled the plugs... Dry. Reeked of gas though, and were covered in white powder. Cleaned 'em and put them back in- no change. Checked spark- quite healthy. But changed the plugs for an OLD set of NGKs, and it lit off. Kinda. Anything below 1500 RPM, it'd miss and go way rich (black, black smoke) until it warmed up, then it idled. Yes, the choke opened up. When I revved it, it would take a few seconds to clear out before it'd run on all 4.

 

Anyhow, Jason showed up, got his stuff, left, and I went to put the truck back in the driveway. No dice... back to the spitting, coughing crap. Now the thing is out of range of my extension cords, and the battery wasn't well charged from all the earlier starting fiascos. So i had to jump it.

 

Well, it would cough at half throttle but wouldn't clear up enough to run without the starter cranking. Gave it a little more gas and it started backfiring, enough to stall the starter. Less throttle... it let off a huge bang out the tailpipe. No throttle... spits and coughs. Smelled like a refinery by now, so I shut off the fuel pump... and it started. But by the time I got the fuel pump hooked back up it quit, so I tried starting again. BANG! Sounded like a gunshot. Try again. Lit off 2 cyls, almost enough to run by itself, give a little more gas... Ka-BANG!

 

Now I can't hear anything, except my ears ringing. People are looking out their doors, and there's smoke... no fire, the smoke was under the truck... with the remains of the muffler. Which used to be a normal oval-shaped one. Now it kinda looks like an overstuffed pillow.

 

Screw this. I got my Ford and pushed the truck into my driveway.

 

Pull plugs. The rear 2 are soaked. The front 2 are bone dry, but reek of fuel.

 

The engine oil reeks of fuel.

 

The carb is soaked, both throttle plates. There's liquid seeping out the base gaskets.

 

Pull carb off, throw a recent eBay carb on (which I had to de-varnish and tighten, it's not pristine but you don't find too many $25 Weber 32/36s).

 

Turn key on, crank- fires off immediately, no cough, no black clouds, no backfiring. Loud, though... no muffler. Doesn't idle, but judging the condition of the carb I suspect it's got a plugged jet. I have others, this one was a quick throw-on.

 

So yes, Webers can go bad. But I completely disassembled the culprit carb and found NOTHING amiss... float floats, float valve shuts, I haven't pulled the jets or the power valve but they don't LOOK bad.

 

What's worse is it had most the symptoms of an IGNITION problem, but that wasn't it at all.

[Jason]

Hi Doug, just got back, thanks for the stuff! So you lit off the fireworks after I left :(? Shoulda tried before I left, we could have pushed it into the driveway. If 2 plugs are wet and 2 aren't is it possible that part of the intake has a blockage?

[DISLEXICDIME]

sounds like your truck is fighting you tooth and nail. you need to show that bad boy who owns who. lol

[datzenmike]

LOL Doug, I did the same with a neighbor's '62 Chev. Tried to start it in the driveway and eventually BOOM the muffler exploded. It runs diagonally under the driver's seat and split it lengthwise and bent the floor up slightly between the pedals and seat. The worst thing was that I had the window down and my ears rang for hours..

[datsunaholic]

Well, after 3 carb swaps and $125 in muffler replacement it's running again. I can't find anything physically wrong with the carb, but it's plain dumping fuel. I put a trashy 32/36 on to test it out (which proved the carb was the cuplrit) but the 2nd carb was so gummed up it woudn't idle nor even run with the choke open even a little. It's gonna need a kit and the jets cleaned up, it's obviously plugged up somewhere.

 

So i put my 38DGAS on... idled OK in the driveway, but wouldn't drop back once I stepped on the gas. Had to close the throttle manually (it'd return most ofthe way but not all the way). Plus it had a massive lag trying to accelerate- like 3-4 SECONDS of dead spot before it kicked in, made it undriveable. Took it off- simply opening the throttle soaked my hands from how much fuel the accel pump shot out. BIG stream.

 

So I used the 32/36 that was off a Toyota Tercel. That one works great, better than the old carb (no more On/Off switch for a throttle). Took it to the muffler shop since the Sheriff's Department isn't too keen on the open-header volume it was producing , hopefully I won't blow this one up in 18 months.

 

At least the weather cooperated. It's cold, but sunny and dry.

[DatDoug]

I dont know if this had anything to do with your rig but this last week with all the rain and then the freezing temps both my weber-fed datsuns are chocking and coughing! I know its the moisture in the gas because they were both running top notch just a las week. I remember the same thing happening to my Weber fed Yota last year at this time. Time to put in the can o heet!

[datzenmike]

When fuel mixes with air and evaporates it absorbs heat. If the air temp is near freezing, this can push the temp at the venturi way below freezing. As damp air enters it collects as frost or ice and blocks flow. The low temperature can super cool the fuel bowl and any water there or entering will freeze and block the jets or tiny orifices.

 

My stock Hitachi has air warmed by the exhaust manifold. The Webers I see don't have this. Webers were built by most North Am auto makers under license. All these had air filters, stove pipes and a vacuum operated valve in the snorkel to regulate the warmed air. I'm sure a ratsun owner could cobble something together.

[71-521]

another thing to remember is this time of year condensation in the tank of water...add some heat or another treatment to help keep water out....

[DatDoug]

You are the man DatMike! I love the way you go into such detail to explain things. Your vast wealthe of knowledge and willingness to share it is very appreciated!:o

[vindats1]

Well I am joining the club...my 521 which was running great, now is also sputtering and also killed the battery trying to keep it running. So we had to put it on the charger and drove it only a few blocks the next day, running rough the whole time. I remember my 410 and also my brother's 510 getting moisture inside the distributor caps causing problems. I used to have a simple metal heater hose for a preheater hose to help with the webers running so cold blooded. Got to love our rain. Nice and green up here all the time. Well we had very lovely sunny but cold weather for two days and of course we were out there working on various cars and driving a convertible.

 

Getting another 320 (my 2nd 63) tomorrow, thanks Bleach!!!!! Well this will give my watch dogs more to do.

[datzenmike]

Well I am joining the club...my 521 which was running great, now is also sputtering and also killed the battery trying to keep it running. So we had to put it on the charger and drove it only a few blocks the next day, running rough the whole time. I remember my 410 and also my brother's 510 getting moisture inside the distributor caps causing problems. I used to have a simple metal heater hose for a preheater hose to help with the webers running so cold blooded. Got to love our rain. Nice and green up here all the time. Well we had very lovely sunny but cold weather for two days and of course we were out there working on various cars and driving a convertible.

 

Getting another 320 (my 2nd 63) tomorrow, thanks Bleach!!!!! Well this will give my watch dogs more to do.

 

To keep damp out from under the distributor cap here's what I do...

 

Get a rubber glove, well not rubber as it will dissolve from gas and oil. Get a synthetic like nitrile and poke tiny holes in the ends of the fingers and thumb. Remove the nipples from the spark plug and coil wires, and push them through the holes (they should fit tightly around the wire) and put the nipples back on. Roll up the sides of the glove and install the wires onto the distributor cap. Roll the glove down over the distributor cap and hold down clips just like a condom :D

 

This seals out damp air, dirt and direct spray. Good for one season. They are so cheap a Dr's office, paramedic... whatever will give them away. They come in pairs so don't worry about making a mistake.:D

[datzenmike]

another thing to remember is this time of year condensation in the tank of water...add some heat or another treatment to help keep water out....

 

Most gas line anti freeze is $5 for 6 tiny 100ml containers... a total RIP OFF! It's methyl hydrate and is available in the paint department at Wall Mart $3.50 for 1,000 ml. Every fill up just slosh some of it into the tank.

 

If you can afford it, keep your tank full in the winter.

[datzenmike]

You are the man DatMike! I love the way you go into such detail to explain things. Your vast wealthe of knowledge and willingness to share it is very appreciated!:o

 

Thanks, Mrs datzen doesn't think so.:mellow:

[hang_510]

To keep damp out from under the distributor cap here's what I do...

no glove, no moisture :? :lol:

 

ive used RTV around the tops and bottom of the plugs and cap and make/add a seal around the base of the cap / distrubutor base.

 

WD40 or IPA(isopropyl alcohol) is also handy in wet environments