Engine Hard to Start -- 1970 Mark III

[CaMarkIII]

I have a 1970 Mark III. It starts and runs fine. If I stop it after it gets warm, though, it won't start, in fact, the engine won't even turn over. If I let it sit for a while and cool down, then the engine will turn over. I think I read here once that I needed to change some battery cables or something to fix this problem. Anybody have an idea what I can do?

Thanks!

[gnowicki_old]

Without checking vehicle when this is occuring, this sounds like a typical starter failure. After the engine is shut off, all items get hotter, due to no coolant flow. This includes everything attatched to the engine, i.e. starter. The starter windings swell and cause the starter to fail. After several more minutes of cool down the fields contract and engine starts. Have it checked for excessive starter draw when hot, this will verify the problem.

[Joe Nemec]

Yes is really sounds like the starter is going bad. You will need to replace it and at the same time if You have not done so, replace the battery cables.

[CaMarkIII]

Thanks for your replies.

I drove my Mark just to check your advice out. I may have given you bad information. When it was hot and I had stopped it, the starter motor does crank a little, stop, and then crank. But never fast enough to start the motor. After it cools down, it's not a problem. I have a new, big battery in the care. Do you still feel it's the starter, or is the starter not getting enough juice.

Thanks!

[Joe Nemec]

It's the starter...

[TonyC]

It is definitely in the starter. A bigger (in amperage, not size) battery will help the car overall, but it won't cure the hot-start issue. The aftermarket starters do not use strong enough internals to withstand the heat build-up. There were several ways to address this issue mentioned recently on another thread. I've done one of those things, and I could already tell a difference.

Here are the biggest suggestions:

1. Replace the starter with a very expensive Baker-built starter, reputed to have stronger components than any other aftermarket offering.

2. Replace the + battery-to-relay cable and the relay-to-starter cable with 1-gauge cables. I've learned that 2-gauge can make a difference, too.

3. Wrap the starter with a foil/fiberglass wrap to protect it from external heating.

Suggestions 2 and 3 can allow you to use a typical aftermarket starter with relative success, so it may not be necessary to go with Suggestion 1 unless you want to.

---Tony

[bunyan]

Hmmmm. This sounds suspiciously like my starter issue. I guess tomorrow morning I should go out and she if mines catches...

bunyan

[Stutz]

Some of the Marks have fairly high compression and as such when they get warm, and if the starter is not really right up to snuff do have a hard time starting. It is no different than many performance engines. The cause is as you say, no circulating coolant. I however disagree with replacing a starter with one from the usual suspects or a simple rebuilt. If it were me I would get a gear reduction model from summit or jegs that has permanent magnets. These are not affected by the heat and do a much better job of turning these beasts over. Of course if you are adamant about originality then this is out but for the most of us this is very beneficial upgrade that costs about the same as buying old technology. No being able to start a car after you shut it off for a couple of minutes is anoying

[mechatech]

Try this http://cgi.ebay.com/ebaymotors/ws/eBayI ... 7967243470
Its in the this thread http://www.thelincolnforum.net/phpbb/vi ... hp?t=11144

[action]

To echo someone's post from above, you may need some diagonsis 1st. Possible causes:

Base timing set too advance.
Carbon build up in combustion chambers causing an even higher compression ratio.
Engine cooling system not at it's peak.
Excessive restistance in the starter circuit - frayed cables, cables too small, starter issues as noted above. Connections not tight or dirty. Also the grounding IS part of this circuit. It is easier for current to travel through a cold conductor than a hot one. Paint on the starter mounting surface.
Oil weight too light and causing pistons to drag on a dry cylinders.

That engine has a PVS valve in the intake manifold behind the goose neck, that retards the base timing via a vacuum line to the second vacuum advance on the distributor. And the blend air door to the air cleaner is very important that is is directing cold outside air to the carb.

PVS = Ported Vacuum Switch

>>>>>>>>>>>>>>>Action

[badwf]

I had a similar problem with a Mark III. It way not be the same issue but you still might want to check it out.

Check the ignition coil. When they are going bad, they will prevent your engine from cranking until they cool down. They will crank fine while cold, but once they get hot...forget about cranking the engine.

[linc64]

David,
First of all, excellent web site!
Thanks for your advice about the coil. My '61 has been doing the same thing (not starting when warm) I did all of the above mentioned things. I figured the only thing I didn't replace was the coil and that had to be the cause of the problem, so that is next on my list. I wish I would have done that first.

[gnowicki_old]

I have never seen a coil cause a no crank condition. Coils amplify voltage for spark. Unless there is some setup I never heard about on your Lincoln, that if the coil goes bad it won't allow voltage to a starter, this is an impossibility in the typical auto. Now as the the problem was described, it was a very slow or no crank after engine hot restart. Sorry, that's a starter, battery, or cable situation. With the starter being the main culprit.

[linc64]

I guess I should have been more clear. The problem I'm having is that the car starts and runs fine when cold. After I drive a while and get the engine really nice and warmed up, the car will only very slowly crank when I try to restart it within a few minutes of shutting it off. As if the battery was dying. When everything cools down, the car starts right up with no problem. I've replaced the starter with a Baker's starter, battery, the cables, have it properly grounded,etc. and it still does the same thing. I'm still going to replace the coil and see what happens.

[Lugnut]

After I drive a while and get the engine really nice and warmed up, the car will only very slowly crank when I try to restart it within a few minutes of shutting it off. As if the battery was dying.

I believe you have a combination of things happening here, not just a single issue. The first thing to consider is the fact a cast iron engine block will become hotter right after shut off and for a number of minutes later because there is no coolant flow, thus requiring a lot more effort on the part of the starter. Second is the possibility of vapor lock due to the engine heat build up. Third is timing; if timing is advanced to the ragged edge or the chain has jumped a gear tooth when the engine is hot it can be nearly impossible to get a start. Maybe almost impossible to get the engine to even turn over as there is no help from fuel being ignited at precisely the correct moment.

After one gets past the issue of a weak starter or battery, the most common fault is timing being too advanced, whether on purpose or from a chain jumping a tooth. Or, in the case of a nylon coated gear, the nylon is now gone so the lost material effectively increases the timing.