The Official 356Talk Forum

Folks,

I’m hoping to get some help narrowing down my path.

Background: I recently put my engine back in with a new fuel pump and clutch, PP, and TO bearing. The car hasn’t been running in about a year after a fuel pump leak but generally seemed to be running fine prior to pulling the engine. It seems very drivable before. It had ethanol free 93 in the tank when it was parked plus stabilizer.

Current Issue: I can start the car right up and warm it to 150-170 deg on the oil dipstick gauge. Sounds fine, revs fine and really tempts you to drive it. Yes, I noticed my brake lamps stuck on the first time I backed out so I ordered that switch. Next I go for a blast out of the neighborhood and don’t get out of the neighborhood before I realize that I’m not really accelerating when I hit the throttle under the load of driving. If you floor it, it almost seems to loose power?

Test and tune so far: The voltage to the coil is 5.98 with the key on before cranking (it is a 6volt car). I verified the static timing lights the test lamp at 5deg before TDC. Replaced Several items such as long lead Bosch wires, Bosch WR6 copper plugs gapped in the middle of the range (.022”), cap and rotor.

Next steps: I plan on valve adjustment and compression test next. I simply ran out of time and don’t have as much time as I’d like between travel for work and spending time with family so, this is something I will have to do a few smaller steps at a time. On the plus side, I can stop and ask if there is an experience that matches the symptoms and a place to look not currently on the list.

Your suggestions: Based on the background, symptoms and what has been checked so far, is there something I should jump right to next?

Thanks,

Once more:
Do a tune up in the proper progression. If that does NOT solve the problem, you'll know it is not one of those things.

Ron LaDow wrote:Once more:
Do a tune up in the proper progression. If that does NOT solve the problem, you'll know it is not one of those things.

Thanks Ron. I will continue working through the tune process and I obviously did not do the valve adjustment first based on time today. I already had the plugs and other ignition parts so I was able to skip to that quickly but I know I need to do the valves next. Following valves, I’ll adjust the carbs and hope something works. Wasn’t sure the valves could cause the type of running issue I had, so I wanted to post current status in case I missed something obvious or could start building my list of secondary checks after the tune is done.

After full tune check battery voltage again. And charging voltage while running. If charging system OK and battery stays lees than 6Volts time for a new battery. And double check that plug wires are going to correct plugs.

Harold, I am going to go for fuel starvation. If you used leaded gas and the fuel stabilizer you may have precipitated some of the TEL out of the gas and coated the jets by using a fuel stabilizer. I have seen nothing written up on adding fuel stabilizer to leaded gas and I never have and never will use a fuel stabilizer unless my cars and ICE engines fuel tanks have to sit unused for at least 6 months.
As a by the way comment I would prefer to put 87 octane in a fuel tank for the winter as it is less highly refined than 93 octane and as such does not degrade as fast. (not as volatile)
Leaded gas is pretty much all that is used universally for piston engine aircraft and I have never read of additives being needed for aircraft tanks and 100LL aviation gas is supposed to be good for 12 month to 2 years without additives.
3 to 6 months is normal life for pump gasoline but can be more or less depending on storage conditions. Low temp and low humidity can extend the life considerably.
Be aware the aviation gasoline has a power RVP than pump gas because of the need to not evaporate at altitude and the fact that avgas tends to sit unused for longer periods of time than pump gas in cars.
Airplane engines have vastly different needs for the chemical composition of the gas than do cars and for this reason I will only use pump gas in my cars and only unleaded gas as that is what my car engines are now tuned for.
I could go on and on about the attributes of gasoline but that would get boring so I will quit now.

David Jones wrote:Harold, I am going to go for fuel starvation. If you used leaded gas and the fuel stabilizer you may have precipitated some of the TEL out of the gas and coated the jets by using a fuel stabilizer. I have seen nothing written up on adding fuel stabilizer to leaded gas and I never have and never will use a fuel stabilizer unless my cars and ICE engines fuel tanks have to sit unused for at least 6 months.
As a by the way comment I would prefer to put 87 octane in a fuel tank for the winter as it is less highly refined than 93 octane and as such does not degrade as fast. (not as volatile)
Leaded gas is pretty much all that is used universally for piston engine aircraft and I have never read of additives being needed for aircraft tanks and 100LL aviation gas is supposed to be good for 12 month to 2 years without additives.
3 to 6 months is normal life for pump gasoline but can be more or less depending on storage conditions. Low temp and low humidity can extend the life considerably.
Be aware the aviation gasoline has a power RVP than pump gas because of the need to not evaporate at altitude and the fact that avgas tends to sit unused for longer periods of time than pump gas in cars.
Airplane engines have vastly different needs for the chemical composition of the gas than do cars and for this reason I will only use pump gas in my cars and only unleaded gas as that is what my car engines are now tuned for.
I could go on and on about the attributes of gasoline but that would get boring so I will quit now.

Unleaded non-ethanol 93 from Adams oil in Powhatan. This is not aviation fuel or low lead. I’ll keep fuel on the radar. Thanks for the reply.

I'm with David and vote for fuel. Were it my car I'd drain the tank and put in fresh gasoline. Remove the carbs, clean the jets with carb cleaner, take off the needle and seats and make sure they're clean. All new gaskets and replace carbs. Five point 98 volts in 6 volt battery that's sat for a while is probably fine. With volt meter attached rev it to 3,000 and see if the generator output is around 7.2 volts.

Richard Shilling wrote:I'm with David and vote for fuel. Were it my car I'd drain the tank and put in fresh gasoline. Remove the carbs, clean the jets with carb cleaner, take off the needle and seats and make sure they're clean. All new gaskets and replace carbs. Five point 98 volts in 6 volt battery that's sat for a while is probably fine. With volt meter attached rev it to 3,000 and see if the generator output is around 7.2 volts.

Will do thanks!

Harold Singh wrote:

Ron LaDow wrote:Once more:
Do a tune up in the proper progression. If that does NOT solve the problem, you'll know it is not one of those things.

Thanks Ron. I will continue working through the tune process and I obviously did not do the valve adjustment first based on time today. I already had the plugs and other ignition parts so I was able to skip to that quickly but I know I need to do the valves next. Following valves, I’ll adjust the carbs and hope something works. Wasn’t sure the valves could cause the type of running issue I had, so I wanted to post current status in case I missed something obvious or could start building my list of secondary checks after the tune is done.

The valve clearances may not cause the issue at hand, and the ignition settings may not also, but by doing that process in sequence, you have removed those from the causes and, further, will not now have to go back and chase your tail if you find the cause elsewhere.
The point can not be made often enough: All of the specific, known, values must be set before you start fiddling with the carbs. Or the pressure in the rear tires. Or the color of the air filters. Or any of the other irrelevancies.
Do the tune in the prescribed sequence. There is nothing arbitrary about this; it is the *required* sequence to tune the engine.
It may not solve the problem; you may have to then look at other issues, but it'll sure save you time and embarrassment if after wasting much time, you find the damn valves are tight.

Harold,

All the guys are correct abort Servicing in the Correct Order and Changing the Fuel

Also you may want to put someone in the car - ask them to push the accelerator to the floor

Are the Carb. adjustment screws hitting the stops ?
You would be amazed at how many guys are driving their cars around without actually experiencing - Full throttle

Make sure that `Full throttle` is obtained without strain on any other part of the linkage

I would use a another source of fuel and test it. then you can rule out the gas as a problem

duplicate.

For the record, the valves are all still at the maestro settings of .006 and .007 for #3 exhaust.

Except the number 2 intake? I’m going to recheck tomorrow. Out of time and worn out from work. May not be thinking straight.

Harold you have a problem. You may have a bent pushrod. I assume you cannot turn the screw any further in and you still have too much clearance? You may have a sticking/stuck valve. Pull the rocker assembly and pull the pushrod and check it. Also why would you make #3 ex clearance .007? Did Harry have a direct channel to a higher authority? Sounds like BS to me even if he was right on many other issues. If Porsche said .006 was correct it is good enough for me and I doubt .001 would make any difference in the real world.

Harold Singh wrote:For the record, the valves are all still at the maestro settings of .006 and .007 for #3 exhaust.

Except the number 2 intake? I’m going to recheck tomorrow. Out of time and worn out from work. May not be thinking straight.

Ok with a clearer head I went back and the valves are in adjustment. Maybe a push rod was out of alignment.

Test drive indicated no power under load but still idles and revs fine when not under a load. Going back through ignition and then the carbs. May do a compression and leak down along the way.