Running Hot!

[Cudajason]

To efficiently run a locked out distributor you need a minimum cam duration of 250* or greater leaning more to the greater side to about 260*. My cam at 272* at 50 ran with 28 Initial and 6* mechanical all in at 900 with idle speed of 1200, as soon as it fired it would go to full timing.  Drag Race only application.

My 318 would hit the stripe at 210 in a 1/4 mile pass, 7000 RPM with a 10.90 ET, by the time I got to the ticket window it would be back to 180*, never put a fan or water on it to cool, out of the cockpit and into my lawn chair ready for next BB Chebby.

************All your heating issues are directly related to the timing events.***********

With that cam you need to have about 16* Initial, 18* mechanical and 14-16* vacuum timing when connected to CONSTANT manifold vacuum at Idle. Not knowing anything about the drive line, car body and gears I can't tell you what RPM you will need the mechanical timing to come in at, probably around 3000 to 3400.

I'm amazed that it even turns over with the timing locked with that little cam? Must be a low compression motor?

From Super Chebby Mag (they finally got something right)

"There's a tiny silver can on the side of most distributors that is easily the most misunderstood component of any distributor-based ignition system. Feared by many, and ignored by many more, the vacuum advance can is an important component of your ignition platform that offers both performance and economy. Leaving it unplugged is akin to throwing free engine efficiency straight down the drain.

To fully understand why the vacuum advance can is a necessity in any street-going car, we need to dive into spark timing as a whole and cover some ignition basics."

Read more here:
http://www.superchevy.com/how-to/additional-tech/1601-everything-you-wanted-to-know-about-vacuum-advance-and-ignition-timing/

@Cuda66  I had read something similar a few months ago, it was discussed on another thread on 340 timing.  It certainly is a different take on things, or at least one we have not discussed since emissions came in.

I agree it cleaned up the idle.  I tried the locked out timing and the performance improved.

My timing was at 21 degrees initial and around 34 total at 2500.

Like I said it sure seemed to work better with the locked out timing. 

But hey, I am always willing to tweak and play with things.  Once I get the rad flushed, I want to see what happens, they I may play with the timing some more.

Jason

[Cuda66]

I'm trying to figure out how it cranks over to start with 34* of timing at crank?
I've been in this business for over 50 years and have never seen an engine with a cam that small bleed off enough pressure to crank and fire at full timing, they always drag the starter down, try to kick backwards, fart through the carb, try to start it on fire or strip the ring gear trying. Especially when hot.

Have you ever done a cranking compression test on it? Have you checked the water in the radiator for Hydrocarbons?

I'd like to see a picture of the ground strap on one of the plugs just to see how hot your combustion chambers are getting. My Old 95 Dodge truck 360 at 9.2:1  likes 16* initial starts on the 1st click of the key hot or cold with a Racer Brown 464/220 at 50 cam. At 18* it drags the starter down to a crawl with the battery cables smoking and won't spin fast enough to fire it off.  Cranking pressure is 168-172 warm.

[Cudajason]

@Cuda66  she cranks over and fires up just fine...hot or cold.

I have never done a cranking compression test...honestly I am afraid to. Motor was last apart 20 years ago. It sat for a while, so not a lot of miles.

No better no worse with 21* timing.

Like i said about 9:1 comprsion maybe less.

Funny I never thought of it as a small cam...sure has a lope at idle.

I have not checked the rad fluid for hydrocarbons, would not know how?

I can pull a plug in the next few days and see what it looks like.

Are you thinking it is lean and that is contributing to the excess heat?

Jason

[Cuda66]

Are you sure that the cam numbers are correct?
Maybe you have a much bigger cam than you think?

If the cam numbers are correct that engine should idle at 750 RPM very smooth and almost no noticeable lope and make about 20" of manifold vacuum.

Vacuum gauge on eBay Item # 282567952295 $11.00
You'll need to stop by NAPA and buy a 1/8th NPT female to 3/16 push fit brass fitting and a a couple of feet of 3/16 vacuum hose... NOT windshield washer hose

If your going to try and trouble shoot this problem you need the basic tools or you can try 20-30 suggestions and in about 3 years maybe you'll figure it out.

You can get a single test strip for under $3 at Grainger
     Item # 4YWX8 Mfr. Model # CTK5029-1 Catalog Page # N/A UNSPSC # 25174004

Compression Tester on eBay for $10 listing number 132042363237

[rebelyell]

In addition to the vacuum gage idea, have you ever checked air/fuel ratio with an external wideband? They make adapters so you can hook the sensor to the tailpipe if you don't want to have a bung welded to the exhaust.

[Cudajason]

Are you sure that the cam numbers are correct?
Maybe you have a much bigger cam than you think?

If the cam numbers are correct that engine should idle at 750 RPM very smooth and almost no noticeable lope and make about 20" of manifold vacuum.

Vacuum gauge on eBay Item # 282567952295 $11.00
You'll need to stop by NAPA and buy a 1/8th NPT female to 3/16 push fit brass fitting and a a couple of feet of 3/16 vacuum hose... NOT windshield washer hose

If your going to try and trouble shoot this problem you need the basic tools or you can try 20-30 suggestions and in about 3 years maybe you'll figure it out.

You can get a single test strip for under $3 at Grainger
     Item # 4YWX8 Mfr. Model # CTK5029-1 Catalog Page # N/A UNSPSC # 25174004

Compression Tester on eBay for $10 listing number 132042363237

Honestly, no I am not sure the cam numbers are correct.  I have had that cam in the car since 92.  It is so old that they do not even make it any more. 

I bought as part of the Edelbrock package back in the day, along with the Torker II intake.  That is a single plane intake and the cam was supposedly designed to worked with that intake.  I changed to the Performer RPM  intake a few years ago in the hopes to get a little more low end...I did.

It is certainly not design to work off idle, it kicks in around 2000 rpm or so.

I actually had to call Edelbrock a few years ago to get the specs as I could not find them online anywhere.  What I provided are what they sent me.

The engine idles in drive at 750 and has a noticeable lope.

I have a vacuum gauge, engine pulls 14in of vacuum at idle.

Thanks for the tip on the test strips...if there is hydrocarbons in the antifreeze what would that signify?

I will do a compression test one day, honestly I am afraid to, I really do not want to pull the engine apart, but I know I need to do it eventually.

I appreciate the feedback, diagnosing is always my weak spot, so I am always happy to learn.  I have no fear of working on it, its just nuts and bolts man!

I have no delusions of grandeur with this engine, I just want it to be streetable.  If that mean replacing the cam or tweaking the timing, thats cool. 

BTW, the torque converter is a factory unit (lock up) so that is not ideal.  The rear gears are 3.22, they work but again not ideal.

Jason

[Cudajason]

In addition to the vacuum gage idea, have you ever checked air/fuel ratio with an external wideband? They make adapters so you can hook the sensor to the tailpipe if you don't want to have a bung welded to the exhaust.

Yep, I have.  I ran a wideband AFR meter up until this year.  I changed exhaust to factory manifolds and mufflers over the winter.  I have a couple of bungs for the O2 sensor bung I have not welded them in yet.

I may try to the tail pipe set up and see if I am lean at highway cruise.  I spent a lot of time the last couple of summers tuning the carb so I was not lean at highway cruise, but I realize that the change to the timing could affect that.

Jason

[jimynick]

Jas, Mopars can also run with either a 6 or a 8 blade WP and I went with the 8 blade hoping for more cooling and mine hardly gets off the lower end of the gauge no matter what the weather is like, with no shroud. It IS a 26" triple core rad and a new core, so maybe not apples to apples here. Just brain (what little I have left) storming. 

[Cudajason]

Jas, Mopars can also run with either a 6 or a 8 blade WP and I went with the 8 blade hoping for more cooling and mine hardly gets off the lower end of the gauge no matter what the weather is like, with no shroud. It IS a 26" triple core rad and a new core, so maybe not apples to apples here. Just brain (what little I have left) storming. 

Fair enough...I have no idea what I have in mine, it has not been apart in a while.

I did get everything back together and took it for a spin.  I am running straight water with a Prestone rad flush product in it (hopping it helps clean things out a bit.

It was bit cooler today than the last time I took it out, car never got above 210 / 215 around town,  It got up to 220 or so in the highway.

Once warmed up, I could see good flow in the rad...the water was moving very well (I think I had too much water in it before which preventing me from seeing the water moving).

I verified the tem with my new temp gun.

The water neck was cooler than the gauge, but the area around the temp sender was very close to the gauge.

The top of the rad was quite a bit hotter then the bottom, same with the top rad hose compared to the bottom.

I think everything is working as it should, however even after a short drive, you can see the same rusty colored sediment in the rad and water.  I still think this is a contributing factor.

It is suppose to warm up a bit over the next few days, and I am off all next week, so I am planning to go for a few spins and see what happens.  The flush the system again with the hose in the hopes of getting as much of the sediment out that I can and see what happens.

@Cuda66 or anyone else, if you thing there is something else you think I should look at or test, please let me know.  We all learn by sharing.

Thanks,

Jason

[Cudakiller70]

Flush and fill till it's clean, may take 2-3 or more times. Did you check your rad cap to see if it's holding pressure?

[Cudajason]

Flush and fill till it's clean, may take 2-3 or more times. Did you check your rad cap to see if it's holding pressure?

Yeah that is my plan.

No I have not checked the rad cap? 

[Cudajason]

Flush and fill till it's clean, may take 2-3 or more times. Did you check your rad cap to see if it's holding pressure?

Yeah that is my plan.

No I have not checked the rad cap?

OK, just ran out and rented a rad pressure tester...

Found three leaks....tow hoses no problem tighten them up and god to go, the third may be an issue.  Have a pretty good leak from the timing cover, high up between the block and the timing cover.  It looks like the gasket failed, it was a trickle, then I touched the gasket and it fell apart, not its a good stream once you hit 15 - 16 psi.   

The rad cap would not hold any pressure what so ever, but I may not have had it hooked up correctly...I will try again in the morning.

I think I will continue with flushing the system and try to get the sediment out, but then I will have to pull apart the front he of the engine.

I guess if I have al that apart, I should consider swapping the very old school cam (which I have thought about doing for years, god I have not even stated and scope creep is already starting!!!

Jason

[Cudakiller70]

Since you may have 1/2 the motor out you should put in  a new hemi 

[YellowThumper]

If the cap is not holding pressure that will definately cause temp cheap. No pressure will then mask as you have found the leaks. I recommend continuing the flush without fixing the the pressure issue. No pressure should allow you to keep it together long enough to get it full clean.
Then the teardown begins. You may also find that the cover has corroded itself away on the inside water ports. Mine was toast. Ended up TIG welding it myself. Figured that it was already scrap so there was nothing to lose.

Mike.

[Brads70]

Well, at least you now know why? Gather the parts and it's a weekend job!  Keep water in it , to flush it out till the end of the " season" and tear it down in the late fall one weekend before it gets too cold? Just a thought?