Hard start problem resolved......finally
Posted: Sat Jun 08, 2019 11:30 am
Since we've had our '72 270 with 413 it has started flawlessly when cold and with great difficulty after resting when hot.
The ignition is electronic --- had been upgraded from points long ago.
I also had a problem of intermittent power loss after stopping the motorhome.
That problem went away after moving the metal fuel line away from contacting the water pump housing. (thanks for info from this forum!!!)
Also added an old piece of hose around that segment of fuel line to insulate and keep it from contacting anything in the future.
That was a vapor-lock problem and it went away completely.
The hard-starting remained.
After the starter began to go out we replaced it with the newer style mini-starter (required some file-to-fit of the electrical terminals but other than that it was easy to install)
The mini-starter was not too expensive and improved how quickly the engine turns over. (DB-Electrical-SND0088 - was like $65)
This helped some but the hot start problem still persisted.
The final resolution to my hot-starting problems was relocating the coil from being mounted horizontally on the intake manifold to vertically in front of the motor nearby the distributor.
My speculation is that the coil was over-heating. (coil is new: both new and old spare coil both work perfectly in new location)
The motor starts perfectly now even after running it hard, stopping to refuel, and then re-starting.
That change made the big difference and I'd recommend it.
Hope this helps if you're having similar issues.
See picture for new coil location.
To relocated I drilled some holes through the metal framing that's around the motor and bolted the existing coil bracket where you see it in the picture.
Note: i also had a look at the grounds and by and large they were in bad shape, especially the main ground.
If you're not 100% sure that your grounds are good then it is a good idea to take care of that.
After doing that i noticed that the motor turns over even faster so i clearly had a marginalized ground.
The ignition is electronic --- had been upgraded from points long ago.
I also had a problem of intermittent power loss after stopping the motorhome.
That problem went away after moving the metal fuel line away from contacting the water pump housing. (thanks for info from this forum!!!)
Also added an old piece of hose around that segment of fuel line to insulate and keep it from contacting anything in the future.
That was a vapor-lock problem and it went away completely.
The hard-starting remained.
After the starter began to go out we replaced it with the newer style mini-starter (required some file-to-fit of the electrical terminals but other than that it was easy to install)
The mini-starter was not too expensive and improved how quickly the engine turns over. (DB-Electrical-SND0088 - was like $65)
This helped some but the hot start problem still persisted.
The final resolution to my hot-starting problems was relocating the coil from being mounted horizontally on the intake manifold to vertically in front of the motor nearby the distributor.
My speculation is that the coil was over-heating. (coil is new: both new and old spare coil both work perfectly in new location)
The motor starts perfectly now even after running it hard, stopping to refuel, and then re-starting.
That change made the big difference and I'd recommend it.
Hope this helps if you're having similar issues.
See picture for new coil location.
To relocated I drilled some holes through the metal framing that's around the motor and bolted the existing coil bracket where you see it in the picture.
Note: i also had a look at the grounds and by and large they were in bad shape, especially the main ground.
If you're not 100% sure that your grounds are good then it is a good idea to take care of that.
After doing that i noticed that the motor turns over even faster so i clearly had a marginalized ground.