Gentlemen, and ladies,

I need some help. I know Penn Dick is probably going to have a hissy fit because I'm working on some new-fangled technology but I got to ask you all anyway.

I'm working on a 1977 (see Dick, I told you it was new stuff...LOL) F-250 with a 460ci automatic. I'm having some starting issues when warm. When cold the engine cranks just fine. Once the engine is up to temp then the engine cranks a bit rough. Like its hard to turn over...... kinda like the timing is way retarded or something.....rrrrump, rrrrrump, rrrrrump

I haven't had a chance to put a timing light on this thing yet. I know in the mid 70's is when Ford started jacking with stuff and detuning these engines (I don't know if I have the original timing set or if its been upgraded). Did Ford have something in 1977 to retard the timing when warm? Ignition module? some kind of vacuum switch? etc

Thanks for any input
Bobby

 

When it is warm and not cranking well pull the coil wire and see if it cranks ok then. If it does you have a timing issue. If it still cranks hard you have a cranking issue. Possibily a starter dragging when hot or bad connections somewhere.

 

Ah yea.....excellent advice

Thank you sir, I always overlook the obvious. I tend to start overthinking the problem and overlook the little things

I'll give it a shot in a bit and see what I can determine

Thanks
Bobby

Added: I just ran outside and tried the truck a few times. Sure enough, when you pull the coil wire it cranks just fine so I'm up against a timing issue.
Thanks again

 

A long shot but easy to check.
Some of that vintage Fords had a check valve in the vac line to the dist advance. If it is not working properly or installed backwards it can hold vac on the advance after the engine is shut off causing advanced timing when trying to restart it. If there is one just pull off the vac line at the dist and try it.
If not probably just the timing set too fast.

 

Hey Bobby,

Try timing the engine with a vacuum gauge instead of a timing light.

When I initially timed my 390 (out of a 72 Ford) every book I look at said to set the timing to 6 DBTDC. But when I finally got a shop manual for that year, apparently that was the setting if a certain piece of Pollution Control junk was installed. The real setting was 12 DBTDC (without the cam and another 2 with it!!!) so I was setting it over 8 degrees off by using the light.

Point is, if you time it with a vacuum gauge, the timing will be correct no matter what the light says. If you slowly continute to fine tune the timing and the idle mixture & RPM with the vacuum gauge installed, you will finnese it into running beautifully.

Here's a link with the procedure for timing using the vacuum gauge:

https://www.ford-trucks.com/forums/8...e-trouble.html

Good luck

 

52 F3,
Thanks for that. I just bought this truck before Xmas and havent had much time to play with it yet. My nephew came into town and has been driving it until recently...ugh. I'm sure that all the vacuum lines are probably about stiff and cracked and I'll end up replacing them all. I'll definately keep my eye out for that check valve.

Jules,
Excellent advice. Now if I can just remember where I put the vacuum gauge (its been a few years since I used it...lol)

Thanks
Bobby

 

Bobby, the 460 also has a specific starter, one that has a solenoid mounted on it like a chebbie. An ordinary Ford starter will usually start them fine when cold, but had issues starting when hot. I went through this with a slightly warmed over 460 until I bought the right starter, presto, no more cranking issues.

 

Jeff,

Hmmm. That makes me wonder. I did have to replace the starter on this truck (front bushing was gone and it would grind occasionally). The starter that came off of it was the standard ford type starter (no solenoid) and the replacement they gave me was the same.

I'm hoping I can get by with a timing adjustment so I can get this truck sold. I'm going to try and mess with it tonight after work
Bobby

 

Bobby,

In my pea-brain I usually associated hard cranking on a warm engine with too much initial advance. Like retarding an old Harley to start it and then advance it to ride ?

I think a lot of the de-tuning during that era had to do with somerthing like a 4 degree timing gear retard ?

Dawg-a-roo

 

Diggity Dawg-a-roo

Hey buddy, you're right. I had it backwards didn't I? I said retarded in my initial description....ugh

You know after forty some years of living with Rectal-Cranial Inversion you would think it would start getting a little easier......nope, its still tough when it flares up

LOL
Bobby

 

Ya know what's even worse? If someone else were to have had this problem Bobby, you would have probably gotten on and typed out a response with all the right answers without a second thought.

I find that when I work on my own truck (as opposed to looking at other folks' problems) there's an extra influx of Stupidosis!

But here's an interesting Quote from my book "How to Rebuild Big Block Ford Engines" by Steve Christ: " Later Fords use a conventional starter, where the gear drive is pushed toward the transmission and into engagement with the ring gear. The later starter can be used with the early "Big Blocks" with no problem. On the earlier engines, the starter gear is pulled into engagement with the ring gear. These starters have a much longer nose, which fits into the bell housing." It appears this change was made about 1965. I don't know if that is applicable or not to this situation, but I thought I'd send it just as food for thought - since folks were talking about starters.

Another interesting note I came across when I was looking at timing specs in my 66 shop manual was that the timing on these big blocks, without pollution control should be between 10 and 12 DBTDC, BUT, you could advance it another 5 DEGREES for better mileage and performance (not sure why Ford didn't just make the extra standard if that was the case), but to re-retard it if there was any knocking. So, you have some leeway on the timing numbers if it was set too far ahead.

Vacuum gauge timing will take care of this if that's the problem - despite the book/timing light settings. As far as the starter type......you're kinda stuck with that.

 

Here's a link to the starter that I mentioned. If retarding the timing doesn't help, this might.

AutoZone Parts Select Store

 

Jules,

Thanks for giving me an out...lol. and thanks for the extra info on the starters.

Jeff,

Learn something new everyday...cool. I didn't have alot of time this afternoon when I got off work. I did check the vacuum line to the dizzy...no check valve. I made quick look with a timing light and sure enough its way advanced. I cranked it back to about 10 degrees and tightened it down. I didn't have time to road test it yet or dig farther into it.
I'll drive it tomorrow and hopefully be able to dig out my vacuum guage and be a bit more precise on the setting.

I had bought this truck on Craigslist awhile back with the idea of fixing a few small things and turning it around to make a buck or two.



Hopefully I can sell it before getting attached to it and wanting to keep it. I love this bodystyle

Bobby

 

With a 460 10 degrees ought to be close enough until you can vacuum gauge it - might even be the right setting. After you do the vacuum gauge timing, shoot it with the light and let us know what it turned out to be!

 

Jules,

Just an update on the timing settings. I dug out my vacuum gauge and warmed the truck up, tweaked the carb and the timing with the vacuum gauge. I went back and checked it with a timing light to see what it ended up at.
I'm setting at an altitude of approx 5400' above sea level. The timing ended up at 18 degrees. I have since backed it down to about 16 degrees.
I've been busy with other vehicles so I havent had much of a chance to play with it since then.

Bobby