Engine hydro-locked ?

[Rock&Roll Firebird]

Hello guys,

seems I have very special moments on my way of turning my Bird back to life. Today I got to the garage after 2 weeks and wasn't able to start the engine. The engine turned but veeery slowly. Seemed it had hard time to spin. The battery is 100% OK.

During the two weeks we were facing heavy rains all over the country and I would say the Bird was exposed to a very high level of humidity during that time. Not sure if that matters but during that time the air filter was taken out leaving the carburetor uncovered and exposed.

Is it possible that the engine sucked the humidity from the air and hydro-locked? And if so, is there any other way of fixing it than taking it out and apart completely?

[scumdog]

I very much doubt it - but if you're concerned you can remove the spark-plugs and try turning the motor over - if there IS water inside the motor you will see it spray out of the spark-plug holes in the heads

From my experience motors that are hydro-locked don't turn over. period.

There is just a solid 'thunk' when you twist the key as the starter engages but that all.

I suspect humidity MAY have affected some of you cars 'lectrics, it would need more that just moist ait to hydro-lock a motor.

In my case it WAS rainwater (no hood, parked outside on a rainy day) and once gas ( parked nose-down on a steep slope and stuck float in carb).

Took plugs out, whizzed the motor over to clear its lungs, screwed plugs back in and viola! - all was well - ok, ran rough for first 10 - 15 seconds...!

[JohnG]

ditto everything Scumdog said.

Taking a plug out is a good habit. You can get some real information quickly.

I would suggest checking electrical connections like the battery terminals, ground to motor, lead to starter. You never know. Take nothing for granted.

A number of years ago I was very close to buying a new starter motor only to find the ground wire to the block was loose.

How do you know your battery is 100% ?

[Astrowing]

batteries have a bad habit of looking good with an open circuit voltage, but due to a bad cell or two, the voltage drops so much under load that it won't crank.
i can't overempahsize the ground wires either. if they are original i`d run new ones and clean up all the connections. I had the same problem with my 61 truck upon reassembly. all those cables should be less than one ohm resistance another problem could be the starter relay, but you can bypass it to check it. also try with a battery from your daily driver if you want to try with another battery.

[Rock&Roll Firebird]

ditto everything Scumdog said.

Taking a plug out is a good habit. You can get some real information quickly.

I would suggest checking electrical connections like the battery terminals, ground to motor, lead to starter. You never know. Take nothing for granted.

A number of years ago I was very close to buying a new starter motor only to find the ground wire to the block was loose.

How do you know your battery is 100% ?

While troubleshooting I took a good modern VARTA battery from my daily driver. The engine at least spin a bit as I wrote. Where can I find the ground to motor terminal?

[JohnG]

the ground wire from your battery should go to the engine block, so just follow it. On mine, it goes to the right front of the engine but no idea if that is original.

Dave has made a good argument in the past for building a new ground to the motor and putting it as close to the starter motor as you can so as to shorten the distance of the (briefly) huge current draw.

In general on old cars, carefully going thru and cleaning all grounds is a good move. The connections can be poor while looking ok due to either rust or paint. This does not take into account the creative but flawed work of previous owners.

Basic rule of old cars: assume nothing.



Weird, off the wall thought: put it in Neutral and see if the speed of turning over changes any. Just a thought. . .

Keep us posted!!

[KULTULZ]

VOLTAGE DROP TEST

[scumdog]

For what it is worth: When I replaced the battery leads on my hot-rod F100 with 'beefier' items it was like I had doubled the battery output and fitted a more 'grunty' starter - if you know what I mean!

I could not believe the amazing change just by fitting larger diameter leads to the battery, well worth it.

Remember:the factory fitted them on a tight budget (cheap!) and it was a looong time ago.

[simplyconnected]

...Remember:the factory fitted them on a tight budget (cheap!) and it was a looong time ago.

Man, you are so right Tom, and they're STILL doing it after all those years. Wouldn't you think someone would get wise? Nope, it's all about profits for stock holders.

[Tbird1044]

Some good info throughout the posts. I agree that you should always check and clean the grounds. These beasts seem to like heavy duty battery cables. You may take the battery to a shop and have them do a "Load Test" on the battery. Voltage can be good but Amps can be low which will cause slow cranking.
Here was the problem I had after purchasing a new battery due to having one that was undersized in capacity. Bought the new battery and it still wouldn't crank when the engine got hot. I pulled the starter and found the rotor bushings completely worn out. I had just replaced them not long ago. These starter drives are somewhat unique and I figure mine was hanging up or staying engaged causing the bushings to wear. I put new bushings in, cleaned the brushes and armature, and installed a NEW starter drive. Things have been great ever since. She cranks like a new car.
Just some info on what happened to me.

[Rock&Roll Firebird]

Hello guys,

I'm paging to you from my garage so any kind of immediate reaction would be greatly appreciated. I just did the following on my 'slow starter' issue:

- cleaned the positive lead connection to the starter
- cleaned both positive connections on the starter relay
- checked, cleaned and measured the ground connection from the battery to the engine block (less 1 Ohm)
- checked the difference between Park and Neutral when cranking (no difference)
- used brand new high-energy VARTA battery
- did not try to start with the plugs taken out from the engine sofar

Unfortunately neither of those steps helped sofar.

I forgot to mention that the last time when I tried to crank the engine repeatedly (and the starter was slow already), there came a slight smoke from the firewall on the drivers side (from an electric isolation I guess).

Can you guys please advise the following?

a) how to perform the voltage drop test (did not find it in the shop manual)
b) how to remove the starter (is there a need to remove the steering?)
c) how to bypass the starter relay
d) is the starter connected to ground by it's mount to the engine block?
e) which connections do you recommend to check/clean
f) can you advise a part number and reseller for the new heavy duty leads to the battery
g) and finally - can you please recommend a new heavy duty starter

Thank you guys. If any other thing pops up on your mind, it would be greatly appreciated. Starting to be a bit desperate...

[Tbird1044]

If there is any question about the condition of the engine, I would pull the plugs and rotate the engine with no compression and see how it spins. It should turn over with little effort, even if you do it by hand using the fan blades.
When I got frustrated trying to remove my starter, I did a google search on starter removal for a thunderbird. You do not need to remove any of the steering components. If I remember you turn the wheels all the way to right and it should give you clearance with a lot of wiggling to get the starter out. I did have to drop my exhaust pipes to get enough clearance.
If you get the starter out, there is a good link in the TRL on how to check and rebuild the starter, or just take it to a starter shop if you can still find one. The bushings were badly worn in mine and it caused the starter to drag enough where it would not turn the engine over when hot. The cold engine was okay as I would get a few cranks before it failed to turn over.
The starter is grounded through the engine block and the engine block is grounded to the battery and also has a separate battery cable to the car chassis.
I wouldn't recommend trying to bypass the starter solenoid with the starter still in the car. You would have to put positive voltage to the starter by putting the 2 cables together, and under load you will get a pretty heavy spark. Starters pull a lot of power. It would be easier to just buy a new solenoid and try that if in doubt. They are not that expensive.
Good Luck
Nyles

[simplyconnected]

Nyles hits on a good point. Electrical current must overcome mechanical resistance. In other words, the harder your engine is to turn, the more current your starter requires to overcome that force. Of course, the starter motor can only produce so much horsepower, and no more.

You said your engine overheated, which tends to warp the metal. That could also make the engine harder to turn.

You indicated that your funds are limited. Knowing that, I hate to see you do this overhaul in small pieces. That process will cost you the most money.

You can remove the starter motor and rebuild it or at least clean the internal components and determine the status of the components. Good luck. - Dave

[KULTULZ]

Can you guys please advise the following?

a) how to perform the voltage drop test (did not find it in the shop manual)

Here 'Ya Go- http://www.engine-light-help.com/voltage-drop.html

[Rock&Roll Firebird]

Thank you guys for your help. I'll be continuing on the starter today. How can the starter be removed - I tried to loose those two bolts but couldn't move the starter a bit after removing them. Any idea?

And how to bypass the starter relay? I'd like to test it as well.

Finally, can you recommend one of these tho new starters (if there's the need)?

http://www.summitracing.com/parts/eca-2073

and

http://www.summitracing.com/parts/tci-313100

Thank you.