Fuel Starved when hot

Hi Guys,

Hoping you might shed some light on a problem I am having. When the engine is warmed up, driving for half hour or more, all of a sudden, car acts like it is running out of gas, sputters and then shuts down. Fuel gauge shows half a tank, so I assumed bad fuel indicator. Call AAA and they come and give me a few gallons. Try to get her started and appears that no fuel is getting to carbs. I take the carb covers off, spray some carb starter in them and she kicks over and runs for a few seconds. Just burning the carb starter fluid. So I let it sit for about 20 minutes and then try again and she starts up, real rough, but running, let her warm up for about 5 minutes and off we go. So this has happend twice so far.

On another occasion, I shut her down after driving for about an hour, come back half an hour later, try to start her, and same thing, feels like no fuel going to carbs. Wait a little longer and let her cool down, and then she starts up, and off we go.

Henry, thinks it may be a fuel line routed to close or sitting on the cylinder covers. I plan on taking her to my mechanic in a couple of days and just wanted to see if anyone had some suggestions I can give him to check out, in addition to the one Henry suggested.

One more thing, after the recent shut down last night, she had been oil tight, and now just started leaking some good amount of oil on the garage floor. Don't know if that helps with any suggestions.

Thanks for any recommendations,

Oz

Gday....I would suspect that the fuel line is tucked too close to a hot spot. You can follow it yourself and see. You may want to look at the fuel filter, is it dangling to close to the motor. If it is you may see bubbling of gas inside the filter. An indication that it is too hot.

Also, is the motor maybe running too warm? If it was you woould have the same fuel issues but also may answer your leaking issue. You have a temp guage on the car?

I agree, it seems like a classic case of vapor lock. Fuel boiling inside the lines. Could be a timing issue causing the motor to run hotter then normal. Some may tell you to insulate your fuel lines. The right way is finding out what is causing it. Do you have a cylinder head or oil temp gauge? They might show a subtle rising of the temp. Or, it you were low on oil, you may have lost the cooling effects of the oil, thus a hotter running car.

Stock mechanical or electric fuel pump?

Oz,

Check you Inline Fuel Filter

Check Fuel Filters in your Carburator(s)

Check Your Fuel Pump.

Check for a "Plugged fuel Line"; Take off Full Pump and Blow Air thru it and listen to Fuel Tank with Fuel Tank Cap off.

These points should get you started.

Jack

We are all waiting with anticipation......

After the filter lines and carb bowls/jets have been checked I'll bet the problem source is at the tank sock, once the engine shuts down the suction that gathered the dirt in the tank and against the sock releases allowing the dirt to settle until restarted and the process repeats.

Wow, thanks guys, will check all the above out and get back to you.

Thanks,

Oz

If it's not vapor lock and has a mechanical fuel pump the pushrod may be too short - check the fuel pressure hot and cold. Also, check your gas tank vent. Also check your ignition timing and fuel m ixture for being too lean.

Oz, I had a very similar, if not identical problem with my TR-6. I'd fill the car and then drive a while and the car "would run out of gas". I finally found the problem to be tank venting. Starting with a full tank and then driving 30-40 miles pulled a vacuum in the tank. Fixing it in the TR-6 was easy, I just reached back and popped the fuel cap on the back panel. Good luck.

Thanks guys, I am taking her in on Thursday and Henry and my mechanic are going to talk and see if they can trouble shoot it.

I will let you guys know what the outcome ends up being. Thanks for all the suggestions.

Oz

OK, here it goes, Just a note Henry is a great guy and followed up with my Mechanic several times to discuss the issues. To bad my mechanic does not thing two brains are better then one, and did not seem to receptive to talk to the actual guy who built the car, so to say the least, I am looking for a new mechanic that is a little more open minded to help and suggestions.

The issue of the oil leak (actually gear oil)was a blown seal on the front of the transmission (near the front cone), lucky they did not have to drop the transmission to repair.

The fuel issue is still a little mystery, we think it had to do with the fuel line routing (getting to hot near the engine) and the mechanical pump. So we have rerouted the fuel lines away from the engine block and switched out the fuel pump for an electric one. We also shorten the fuel venting tube off the tank, now ending up in the front wheel well. It ran the length of the car to the back, but Henry does that for wet weather climates to prevent water in the tank. Not a real problem in So. Cal.

I plan on making a run from Dana Point to Newport Beach tomorrow morning and will hopefully not get any fuel cutout issues. By the way, Henry also stepped up to bat on these repairs, just a great guy and businessman.

Thanks,

Oz

Good news Mr. Oz, hope your drive goes well.
Tried to look at your pictures, and was getting an error msg.
Anybody else having this problem?

Good News, Oz.....glad it all worked out.

P.S: I can't see your photo's either......

"switched out the fuel pump for an electric one"

I hope that you went with a Holley, rotary, or quality high performance pump rather than the loud little square piece of junk that they offer for sale everywhere these days. It's made by Facet and sold under a bunch of names, but in the end it'll always fail on you. They're VERY susceptable to heat and only last a year or two under regular use. The biggest problem is that they don't put out a constant pressure (which duals NEED) and drop pressure as they age, so you actually only get 6 months of quality service out of them, followed by a slow decline and eventual failure. For me it happened about a mile from the Litchfield VW show!

Just a caution . . .

Luck,

TC

Well, you guys are not going to freaking believe it. I am going to go buy a lottery ticket, because my luck has to be ready to change!

So I get up today to take her for a spin up the coast (beautiful sunny day too!). I smell some gas in the garage, and pop the engine lid, the new electric fuel pump (EMPI) is leaking all over. I check the fuel lines in and out and they are not leaking at all. It is actually leaking from the large nut where the in line goes into the pump. Looks like a bad pump. I did not want to take her out for a drive, with the fear the fuel would leak onto the exhaust and then I would be roasting marshmellows on the side of the road.

As I look underneath the car, I notice a nice puddle of gear oil again! It is coming from the transmission, right were the rear sway bar comes across, dead center of the car. So to say the least, back to the mechanic it goes this week. I will try not to ring his neck, I guess I know its a car and sh_t happens, but his cocky attitude like he knew what was wrong and did not want any advice from Henry really now has got me a little steamed.

Well I have already paid him, so I will get him to give me another fuel pump and see if he can actually fix the transmission leak, then I am off to find a new mechanic.

I just want to get back on the road and start enjoying my speedster!

Sorry for the rant. By the way I did post some pictures of my car.

Wish me luck next week, hopefully I will not make the newspapers for killing a cocky VW mechanic,

Oz

Mr. Oz, I feel your pain.
May I suggest you follow TC's advice on the fuel pump - also, many fuel pumps should be mounted at the gas tank as they are "pushers', not "pullers".

Your pictures look great, and I noticed you're the first person I've seen with a "Super 90" script on the rear of your car - I bought the Super 90 too, but am waiting to paint my car before installing.

Good luck, and keep us posted.

Oz, I was just looking at an Empi fuel pump - is it leaking where the threaded barb screws into the fuel pump? If so, maybe a little Teflon tape on the threads of the barb, re-tighten.

Well today I called around and found a new friendlier VW mechanic. Seems to really know what he is doing, 30 years working on VW aircooled engines. Only him and one helper, he works on all customer's cars himself. Says he does not trust anyone to do the job right, except him. He said due to the fact it is only him, repairs could take a day or two. OK with me as long as it is done right.

He did not like the idea of the electric fuel pump at all, and suggested getting a better mechanical one. He said when the electric one goes, you will be stranded on the road. He also said, if he were to put an electric one in, it would be in the front, by the fuel tank, where gravity would flow to it. And he certianly would not mount it in the engine compartment over the exhaust system where it is now.

Well, I am going to take it in tomorrow morning and see if he can fix the fuel problem and transmission leak.

I will keep you guys posted on my continued saga.

Oz

Gee.....

Your new mechanic sounds like one of US!

Oz, just a note for AFTER you get everything properly sorted and running again. I previously had my gas vent hose terminating in the front wheel well, as you mentioned early on. With a full tank, I got quite a bit of gas fumes in the cockpit. Less as the tank emptied. Finally, I extended the vent hose to a spot below the chassis (still in the front wheel opening. This eliminated nearly all gas fume problems. This may work for you also.

When VW mechanical pumps get tired they leak gasoline into the sump, thinning the oil. A good quality pressure-regulated electric pump like the one from CB Performance is a much better choice.

Good quality pump is the important part. The Facet pump does not seem to be too bad.

I have always mounted the electric pump just under the gas tank at the front.

If you are worried about the electric pump failing, run it through the mechanical or run two electric, but I wouldn't and I wouldn't expect problems.

We used to run two in-line electric pumps when we raced off-road (ie: Baja 1000 etc...)

Hello,

I had the ame problem. It sounds like vapor lock which is like the others have said above. The gas is getting to hot and is phyically boiling before it has a chance to reach your carbs. I went to a speed shop and bought a high temp insulated hose primarily used in race cars. I inserted my entire gas lines in this and it has stopped my vapor lock issues.

Oz,

Saw your post on SpeedsterOwners.com about your "new friendly mechanic". I live in the area and would like to get his contact info. He sounds like a person that I would want to work on my speedster.

Thanks!

Chris S.

Mark,

It was for sure vapor lock, the fuel lines were running up against the enging block. My new guy Pete at VW Specialist (949)500-1573 (thats for you Chris)rerouted the lines and insulated them with some fuel injection hose. I took her for a long hot drive Sunday and no fuel cut out or vapor lock. She actually is running really well (knock on wood). The only problem I have left, is we are having a hard time finding the transmission oil leak. We cleaned everything off with carb cleaner, got her dried off and I have put about 50 miles on her. She is leaking everytime I stop. A good amount of gear oil. Enough to puddle and run across the ground. I was hopeful it was due to over filling of the trans oil on first 600 mile change and oozing out of the vent hole (Bonehead first mechanic may of over filled). But it seems like a seal or gasket may have blown. I am hopful we don't have to drop the trans to fix. I am going to put a few more miles on her and see if she stops leaking. I know if I drive it long enough, it will stop leaking due to no oil being in the transmission, so I am trying to avoid that. But I will take her back to Pete in a few days and have him check the gear oil levels and see if we can find the leak.

Pete has been great, very receptive to calling Henry and asking for his input. I am still waiting to hear back from Henry on what his impression is of him. He seems knowledgable, friendly, and honest. I hope I get this transmission issue fixed before Knotts, I will keep you guys posted.

Thanks,

Oz

Oz: The fill hole on the drivers side of the tranny is also the "check for full" hole. It has a BIG hex plug in it, and you fill it with oil til it starts to run out of that hole, then put the plug back in - all this done assuming that the car is level (I put mine up on jack stands to get it level but off the floor - all that cause I'm too poor to afford a car lift in my garage - LOL!).

Some guys (like me) use teflon tape on the plug, while others use thread sealant, but you have to put something on that plug, and also the drain plug on the bottom, to keep them from leaking (ask me how I know....)

gn

Gordon:

Pete has put my car up on a lift and we have gone over the transmission in detail. The leak is not coming from the fill plug or anywhere on the bottom of the transmission. It actually looks like it is coming from the top. Where the vent hole is or along the gasket. There seems to be some donut foam/rubber ring at the top of the transmission that is soaked in oil, so I think that will be the next logical place to check. I am going to drive her for a few more days and then take her back in to check to see if we can find the leak. Will keep you posted.

Thanks,

Oz

Some top trans breathers must be installed in the correct orientation or they will spit oil out.

Talked to Henry today and he is going to speak with Kevin at KCR Transmissions. He is the one who built my trans. Will see what he suggests. His shop is in Riverside, CA, only about an hour away. So I might even end up driving to his shop and letting him take a look and see what he thinks the solution might be.

Thanks for all the input.

Oz

Oz,

Say hello to Kevin for me. He is a stand up guy that built the tranny for my 56 Ragtop (RennKaferStyle). He was in Sonoma a few weeks ago
to pick up cores at my buddy's "shop".

BTW, how is the registration process going?

Patrick

Pat,

Got my pink slip/title in the mail a few months ago. So I am good to go. Just got to get the trans leak figured out. I know I will get everything dialed in, all in good time.

I will give Kevin a hello for you. But hopefully I will not have to have the pleasure of meeting him, but will see. Still leaking as of today.

Have a great day,

Oz