No power top end

Greetings everyone! My name is Greg and I have a 1960 Ford F100 with a 460 in it. The 460 came out of a late 80's/early 90's E350. It has been giving me so many problems to get right, but it seems like my last issue has beaten me. I have replaced carb twice, water pump, radiator, fuel pump, exhaust, etc.

It will start when cold but not when warm (think issue is a throttle body spacer). The worst issue I am having is that when i run it more than 65 mph it has absolutely no power and wont accelerate. My mechanic is dumbfounded and is looking at the valve train but it doubt it is that. I have checked timing and adjusted, recleaned the carb, installed new fuel pump... dont know what I have left to look at. Any suggestions will be really appreciated as I haven't really seen anything else on the forum addressing this issue. Thanks again.

Have you determined if your "no start when hot" condition is electrical (as in no spark) or fuel related (maybe flooding after shutdown)? Do you smell fuel when attempting the hot start?

Just for consideration....a cold engine will like a rich (as in flooded) condition much better than a warm one. Just spitballing here.

Also, since your engine was likely a fuel injected deal, what parts were used to make the conversion to carbed? What distributor and ignition system are you using?

What distributor, and ignition are you using...hopefully not the EFI as the sensor manipulation can be daunting, if you are I would try an older Duraspark.

The no start when hot issue does not seem to be an issue as it will fire/misfire.  My mechanic seems to think it is a carb issue.  It gets a pretty violent misfire  when it happens and has chewed through at least 1 filter element.  I think the carb is getting excess heat from the manifold and boiling the gas.  I  had a spacer on it with the last carb but did not change it over when i bought the bigger Edelbrock.

It has an MSD coil and a Edelbrock carb, I will have to go out in the morning and check the exact specs on the distributer.  I changed the cap and experienced the same issue.

I bought the truck with all the work already completed so I am not to sure on the details of the EFI conversion. What might have been left out with the previous owner?

im not sure if this will help in your situation.a guy I use to know changed his efi motor over to a carb deal.he had trouble with it shifting and running correct until he located the tps sensor.he used an oms meter to read the oms at a certain opening then taped it up in that position.it ran a lot better with the gm style distributor also.he had a 550 holley that didn have the isolator spacer under it that had a tendency to boil the fuel once you cut the motor off.

TPS sensor may be the issue... never thought of that. It is almost like there is a rev limiter at high rpms so this would make sense.

I spoke with my mechanic today and in his opinion he thinks he needs to check the valves to ensure they are sealing properly.  He also stated the high speed power loss might be that the timing chain is worn and slipping at high speeds.  This doesn't make sense to me because if it slipped it would always be out of timing and that doesn't seem to be the case.

He also stated that the Edelbrock carbs are not what they used to be and suggests that it could be a vacuum leak out of the brand new carb.  He will test for that also.

I put on a spacer but still have the hard hot start issue.  The distributor seems to be a stock model, nothing special. Any help is appreciated.

I am not able to upload any pictures, it seems my max size allowable is 0 mb.

gssickels wrote:I spoke with my mechanic today and in his opinion he thinks he needs to check the valves to ensure they are sealing properly.  He also stated the high speed power loss might be that the timing chain is worn and slipping at high speeds.  This doesn't make sense to me because if it slipped it would always be out of timing and that doesn't seem to be the case.

He also stated that the Edelbrock carbs are not what they used to be and suggests that it could be a vacuum leak out of the brand new carb.  He will test for that also.

I put on a spacer but still have the hard hot start issue.  The distributor seems to be a stock model, nothing special. Any help is appreciated.

I am not able to upload any pictures, it seems my max size allowable is 0 mb.

The valves fix them self when cold/ warm engine temp?????!!!!! Plus the timing chain tightens up ( slipping chain!!!)at the lower temps. vacuum lealk also?

what type of fuel pump?

try driving with the gas cap loose.

I sense your sarcasm and feel the same way.

I have driven with the gas cap loose and have experienced no change in the performance.

Will check the fuel pump in the morning.. i should have it in my records.

gssickels wrote:The no start when hot issue does not seem to be an issue as it will fire/misfire.  My mechanic seems to think it is a carb issue.  It gets a pretty violent misfire  when it happens and has chewed through at least 1 filter element.  I think the carb is getting excess heat from the manifold and boiling the gas.  I  had a spacer on it with the last carb but did not change it over when i bought the bigger Edelbrock.

It has an MSD coil and a Edelbrock carb, I will have to go out in the morning and check the exact specs on the distributer.  I changed the cap and experienced the same issue.

I bought the truck with all the work already completed so I am not to sure on the details of the EFI conversion.  What might have been left out with the previous owner?

gssickels wrote:I spoke with my mechanic today and in his opinion he thinks he needs to check the valves to ensure they are sealing properly.  He also stated the high speed power loss might be that the timing chain is worn and slipping at high speeds.  This doesn't make sense to me because if it slipped it would always be out of timing and that doesn't seem to be the case.

He also stated that the Edelbrock carbs are not what they used to be and suggests that it could be a vacuum leak out of the brand new carb.  He will test for that also.

I put on a spacer but still have the hard hot start issue.  The distributor seems to be a stock model, nothing special. Any help is appreciated.

I am not able to upload any pictures, it seems my max size allowable is 0 mb.

Use photobucket for the pictures html link.

The vacuum leak situation is easily diagnosed (ususally a surge type miss, put a gauge on it), timing chain right idea but that typically equates to erratic timing (every time you check it its different), backfiring through the carb can be many issues (broken valve spring, cam lobes missing, timing off, etc) I do not often do this but I will say it again look at the ignition system if it is an EFI box/dist and there was a resistor soldered in that failed, it would no longer be bypassing the sensor (or telling it to add timing), you would then have to find the failed resistor and replace it or change the dist/ign module to a non EFI combo.

Find another mechanic.

Anyone have any suggestions of a reputable shop in Ft Myers, Florida? I am on my 3rd mechanic here.

I am pulling the truck out of the shop it is in now. Going to be driving to my sons up in New Orleans... anyone know a good tech there that is familiar with these engines?