Hard/Slow Crank When Hot

Hey folks,

I've been having this issue that I've been meaning to seek advice for. When I shut my engine down, and go to restart it, it often LABORS to crank when hot. Imagine how an engine with a bad battery sounds...it acts just like that. Most times it will eventually start while cranking slowly, but other time's I've either had to jump start it, or wait until things cool off. When the engine is cool, it cranks absolutely normally. This leads me to think its NOT a bad battery. The car cranks fine when cold. Its only problematic for hot starts...like if I run it to the store...or shut the car off while getting gas.

One item that I'm leery of is the way my PCV system is plumbed. My pcv valve is installed on my valve cover, instead of the intake manifold. The PCV hole on the intake is plumbed to the breather element on the air cleaner. This is not normally how the system is routed. Not sure why my installer went this route, but it seemed to work, so I never relocated it. Could this be a contributing factor?

Here is a video from today. I let the car idle for a while to get to regular operating temps. This is what it does:

https://www.youtube.com/watch?v=_YQ1QpvT-SQ

 

about 20 minutes later...

https://www.youtube.com/watch?v=UTS3mbQBcTc

 

Sounds like the starter. It still seemed to labor on cranking in the second clip. You can try cleaning all the connections. Many auto parts stores have a battery tester that can measure starter current draw. Check it both cold and hot.

 

Thanks. The starter is new. Talking to a buddy here, he's suggesting I check the battery first.

 

Check battery and connections (at battery and starter), battery cables for high resistance, timing too advanced, weak starter, missing heat shield on starter (if it originally had one).

 

In searching, I found a very similar thread with great advice and tips...

http://www.v8buick.com/showthread.p...ghlight=starter+turns+slow+when+engine+is+hot

I'll be checking the basics first...

Thanks,

Langston

 

Recent change to more initial timing?

 

Nope, never made any changes to the timing. And the distributor is still snug in place.

 

Thanks for the insight. When I get the time, I will begin checking everything systematically.

As always, the advice is much appreciated.

 

Had a similar experience with one of my Gran Sports a few years ago. A new battery cured the problem. :TU:

 

That could be the problem, but my experience with batteries these days is that the car started to get you to work, and failed to start the car again. It used to be that batteries failed gracefully- it seems to be taking longer to start over a period of a couple of weeks, and you could tell. Nowadays, when I have a battery that is four years old, I have it checked, frequently. I'd much rather "waste" $20 Vs having the wife or spawn out somewhere in the (basically non-existent in Southern California) rain at night with a dead battery.

 

Listening to the videos, it sounds like a weak battery.
In the second video, its still cranks VERY slow.
It looks like you have a '75 '76 LeSabre/Electra? The 455's those years were only 7.5 to 7.6 to 1 compression, that engine should crank relatively fast:Smarty:

 

I'm having the battery tested today. It is a '76 Electra. The engine is rebuilt, 9.4:1.


Also, I see some evidence of the battery cable being worn near the grounding point on the engine. I'll replace that as well.

 

If I remember correctly those years had COPPER CLAD ALUMINUM CABLES from the factory. They draw EXCESSIVE amperage & MUCH WORSE with age. Even new they were troublesome. Replace with a MINIMUM 2.0 gauge cable.
Test the battery 1st!!!

 

Just a thought... I'm not sure what new means for the starter -- if new means rebuilt -- I'm suspect. I've had some poor experiences with rebuilt starters that had very worn cores -- they drew too much voltage when they got hot. (Maybe the prior starter exhibited the same issue so that precipitated the swap??) If you chase this and don't find an obvious solution like a battery or a cable -- I might resort to swapping the starter. I know what a pain that can be so I would advocate following some robust troubleshooting prior. I'm not a fan of jumping to conclusions only to waste time and money guessing...

 

I vote for battery/cables too....
Here's a blog post I made when I had the exact symptoms
Take a look at the positive cable as it runs though the plastic block on the side of the motor, mine was in horrible condition

http://72buickgs.blogspot.com/2014/09/what-ride.html

 

So I had the battery tested today at the local Advance Auto Parts. He said the battery was ok...but needed to be charged (which is slightly contradictory in my opinion). The CCA measured in the 500 range, and the battery is rated at 775 CCA. I asked for a print out of the results, but of course the printer wasn't working. Also, they didn't have the proper battery cable in stock for me to swap that out.

I went ahead and hooked up my multi-meter to the battery and it only read 12.35v, which is low in my experiences.

I'll charge the battery in the interim, but I'm probably going to just replace it, and the worn cable at the same time. Also gonna right my PCV system.

 

Just wanted to share...I'm just curious if this is a new problem or something that you've always had? Some eons ago when I transplanted a 72 Buick 455 into a '81 Regal, I've had this same hard to start condition as you described. With the puny V6, I've never had this problem but this problem surfaced after the installation of the 455. Sadly I never resolved this issue and removed the 455 prior to junking the rotting carcass. I'll revisit this problem whenever life slows down enough for me to transplant this engine back into something. For now I can brow beat...in my case, I'm leaning towards ignition timing that's if everything else that was mentioned checks out.

 

It began after the new engine was installed.