First Ride of the spring, and Carb drainback...

[davepl]

I took my truck out for it's first ride of the spring, and it has sat 3-4 months I suppose.

It took a long time of cranking to get fuel up to the carb bowls, and then it was two pumps and it fired right off.

I didn't like all that cranking (maybe 10 seconds total?) because I have a flat tappet cam and, zinc additives or not, I'm scared of wiping a lobe.

Is it normal for these to drain/empty like that so that the line is dry and it takes a while to get fuel? Most everything else I have uses an electric pump, so I honestly don't recall!

[RichardJ]

The pump gas you are buying is probably E10 and it evaporates very fast on vehicles with no EVAP system. Carb bowls vented to the atmosphere can evaporate dry in a few weeks.

[cleszkie]

3-4 weeks is a long time to expect gas levels to remain good in your bowls. However, if you are running a Rochester Q-jet, these have been known to get leaks in the factory installed plugs in the bottom of the bowls. When leaks occur, fuel in the bowls drains down into the intake manifold over time, emptying the bowls. I had this issue, and ended up buying the bowl plug sealing kit sold by Cliff Ruggles on his website. Google Cliff's high Performance and you will find it.

I wouldn't worry about flattening any cam lobes during cranking. The oil pump is still moving some oil, and the RPMs you are turning during cranking are pretty low.

[Already Gone]

I don't know what you have for a carb but I started my truck up last week after its Winter slumber with no issues. I parked it about the 3rd week of October full of gas with some Stabil included. I think itbmarch 27/28th I unhooked the Batter Tender, checked the oil got in, pumped the gas twice and when I turned the key she started right up on the automatic choke. My truck engine with the exception of a complete Pertronix Unit is stock including the carb.

[El Dorado Jim]

I have an additional in line electric fuel pump on a switch for reasons like this,it is mounted on the frame under tyhe truck by my gas tanks, I have two saddle tanks and got rid of the in the cab tank... turn on the pump for a minute or two, gets fuel up to the carb and not cranking on the engine hardly at all...you could mount one underneath your truck also...electric pumps are meant to pump or push gas , so should be mounted fairly close to your tank....

[Steeveedee]

Originally Posted by El Dorado Jim

I have an additional in line electric fuel pump on a switch for reasons like this,it is mounted on the frame under tyhe truck by my gas tanks, I have two saddle tanks and got rid of the in the cab tank... turn on the pump for a minute or two, gets fuel up to the carb and not cranking on the engine hardly at all...you could mount one underneath your truck also...electric pumps are meant to pump or push gas , so should be mounted fairly close to your tank....

Yup. You really need an electric fuel pump if you run saddle tanks. It helps when you're not paying attention to the miles you've put on a saddle tank, and suddenly the truck starts to surge...and you're on the Pacific Coast Highway with a truck that has starter heat soak that takes a half hour to cool off! The people on that road behind you will not be happy with you. I was lucky enough to feel the first surge and turned the valve quick and then flipped the electric pump switch on in time. It wasn't my truck at the time, so I wasn't used to all the ins and outs of it. The electric fuel pump also helps with starts after you vehicle has been sitting for awhile.

[HO455]

As long as your engine is well broke in you don't have to worry about your cam during start up. If you want some piece of mind after a long storage you can take a small funnel and refill the float bowl by pouring about four ounces of gas into the carb bowl vent. Then reinstall the air cleaner before starting.

[joeydurango]

On top of evaporation, mechanical fuel pumps will sometimes let some fuel drain back down the pump>carb line after they sit for a bit. I have a newly rebuilt carb and a new AC Delco fuel pump, and if my truck sits for two days, it fires right up on the first or second pump. But if it sits for 5-7 days, it may take several pumps and ~5 seconds of cranking to get it going.

If your truck has been sitting for 3-4 months, as you say, there's no way you're going to have fuel at the carb given evaporation and fuel pump bypass... I'd start wondering about priming the oil pump before a start once it's been sitting that long.

[Tom Vogel]

Originally Posted by cleszkie

3-4 weeks is a long time to expect gas levels to remain good in your bowls. However, if you are running a Rochester Q-jet, these have been known to get leaks in the factory installed plugs in the bottom of the bowls. When leaks occur, fuel in the bowls drains down into the intake manifold over time, emptying the bowls. I had this issue, and ended up buying the bowl plug sealing kit sold by Cliff Ruggles on his website. Google Cliff's high Performance and you will find it.

I wouldn't worry about flattening any cam lobes during cranking. The oil pump is still moving some oil, and the RPMs you are turning during cranking are pretty low.

^^^^^^^This

[67 chevelle]

Originally Posted by HO455

As long as your engine is well broke in you don't have to worry about your cam during start up. If you want some piece of mind after a long storage you can take a small funnel and refill the float bowl by pouring about four ounces of gas into the carb bowl vent. Then reinstall the air cleaner before starting.

[68Gold/white]

Quadrajets are not all created equal. The mid-70's and newer units tend to leak little if any. They have lead plugs in the well openings. It would likely mostly depend on what Q-Jet you have.
Modern gasoline even without ethanol is a whole different animal than gasoline that was in use when most of our classics rolled out from the factory. The stuff evaporates very easily.

Every vehicle has it's fuel lines routed differently underneath each vehicle. Some vehicles , making starting different for each.

When I start my old car, I first spin the engine, BEFORE I pump the acc. pedal, just to get gas TO the carb. Then I pump it twice, to try to start it. If it does not hit, I turn it over some more, then pump twice again.

Usually the second two pumps gets it going.

Be careful, if you sit in the car and spin the engine over and continuously pump the acc pedal, it's one of the best ways to flood an engine.

You just have to think of what's going on in the process of fuel delivery.

As for the O.P. I think you have no problems to worry about, just a normal thing after having sat for an extended time.

[davepl]

Originally Posted by cleszkie

3-4 weeks is a long time to expect gas levels to remain good in your bowls. However, if you are running a Rochester Q-jet, these have been known to get leaks in the factory installed plugs in the bottom of the bowls. When leaks occur, fuel in the bowls drains down into the intake manifold over time, emptying the bowls. I had this issue, and ended up buying the bowl plug sealing kit sold by Cliff Ruggles on his website. Google Cliff's high Performance and you will find it.

I wouldn't worry about flattening any cam lobes during cranking. The oil pump is still moving some oil, and the RPMs you are turning during cranking are pretty low.

Pretty sure I had my well plugs epoxied when I had it rebuilt, if that's what you mean, but I can't say for sure.

I only have about 400 miles on this engine so I'm still a little sensitive about the cam lobes. The oil pump moving oil does the cam no good, because the lobes are only splash lubricated. But they survived! I have two bottles of CamShield in the current mix.

[HO455]

Originally Posted by davepl

Pretty sure I had my well plugs epoxied when I had it rebuilt, if that's what you mean, but I can't say for sure.

I only have about 400 miles on this engine so I'm still a little sensitive about the cam lobes. The oil pump moving oil does the cam no good, because the lobes are only splash lubricated. But they survived! I have two bottles of CamShield in the current mix.

In the interest in cam survival I highly recommend putting a quick thousand miles on it. If you don't have time just call I'll come up and give her a good run in.

[LongBox]

I have a hunch that a lot of us worry about cam lobe wear on flat tappet engines these days. The change in engine oil formulations is probably one of the main reasons that GM went to roller cams in the 90s.

Look at it this way: if your cam develops a flat lobe or two, you've got the perfect excuse to put in a roller cam!

[Steeveedee]

Originally Posted by davepl

Pretty sure I had my well plugs epoxied when I had it rebuilt, if that's what you mean, but I can't say for sure.

I only have about 400 miles on this engine so I'm still a little sensitive about the cam lobes. The oil pump moving oil does the cam no good, because the lobes are only splash lubricated. But they survived! I have two bottles of CamShield in the current mix.

Your cam bearings have oil holes and allow oil to be introduced onto the cam journals. If that were not the case, it would have wiped those bearings within minutes of startup. If you broke the cam in properly, it's broken in, and even putting low mileage on it shouldn't affect it.

[davepl]

Originally Posted by Steeveedee

Your cam bearings have oil holes and allow oil to be introduced onto the cam journals. If that were not the case, it would have wiped those bearings within minutes of startup. If you broke the cam in properly, it's broken in, and even putting low mileage on it shouldn't affect it.

No one is talking about wiping bearings, just lobes.

The bearings are pressure-fed from the oil galleries.

The lobes are not. They receive only splash lubrication from crank windage and what little drains out of lifters.

Look at it this way: if your cam develops a flat lobe or two, you've got the perfect excuse to put in a roller cam!

Sacrilege! I want every one of my 310hp and not a pony more! :-)

[El Dorado Jim]

install an electric fuel pump, problem solved