Hi All, My '78 L-82 pace car suffers significantly from heat soak hot start here under the Spanish sun with most days in the 90's. Having read a lot on this forum about causes and solutions, I've for now wrapped the exhaust a few days ago. Still burning off the smoke and still early days to find if that did the trick (bit of a scare at the gas station yesterday when my wife yelled 'there's smoke coming from under the hood, we're on fire', to learn later that the smoking is part of the process of curing). The original Delcro starter has taken a beating over the years though (see photos) so I decided to replace it with a mini/gear reduction starter. Most posts I read are somewhat older and I'm wondering if any of you want to way in on what options to go for: Tuff Stuff, Powermaster, CVR-5323, etc. Your insights are as always invaluable and appreciated.

 

I have a mini starter and headers with no issues.
Is your car running properly? Air fuel mixtures can raise exhaust temperature also improper timing.
Is your cars cooling system working well? In hot climates like I have here in Florida I run a 160 degree thermostat.

 

Hi, The car seems to be running fine. It's new to me and I have nothing to compare to in a V8 version. I did find the heat in the engine bay significant, especially compared to my little Alfa Spider of same age (half the cylinders, half the car weight, but a heck of a lot of responsive drive fun. the engine water temp gauge indicates a temp of well below the 200 mark, around 180 I would say. Oil Pressure just below 40. Car runs smooth at correct idle speeds and accelerates fine, albeit somewhat more sluggish than I had hoped for (the Spider has the Vette beat by quite a bit in terms of throttle response).

After a 30 minute mostly slow city start/stop drive this morning with a 3km faster bit and 1km uphill section at the end this morning I measured the temps: 556-624 at the manifold, 392 at the heat wrapping in the bend around the starter motor and 180 on the starter motor itself (which I found surprisingly low considering the other temps). That's with the heat wrap in place and I didn't actually measure any temps prior to installing that so can't compare. Outside temperature probably in the low 80's at the time.

Does that all sound reasonable?

The good news was that the car started again after I turned it off in the garage, which it has been one of the heat soak moments in the past).

 

Hopefully you're OK with the Hurricanes. We have friends in Sarasota and on Tampa Bay. Look after yourself, be safe.

 

wow, your car is nicely original, very nice. you even have the oem solenoid heat shield.
Before you change out starter, it appears that the pipe is very close to the starter. It does not look like OEM pipe bends, you may want to start there.
That DEI wrap does work well, you may even wrap tighter (closer wraps) to improve heat protection as well.

here is my thread on similar situation with starter and mini starter attempt 79 L82 which should be same.
Also note there are brown bakeolite solenoid caps that were OEM and were to be able to withstand more heat i think. Solenoid can be the issue as well..
Good luck!
https://www.corvetteforum.com/forums...rt-79-a-2.html

i also took some pictures under car to compare.. forgive the filth, its been about 4000 miles since under body clean up inspection..






I think the L82 got a high torque starter, you can tell if you need a spacer for the hot lead tab into starter from solenoid.

 

Thanks we are across the state near NASA so we are in a pretty good area.
Reach out to Lars for his tuning papers,, following them can increase power noticably. For little money. The L-82 is a good starting point.

 

Thanks! yes, I do have the high torque starter. The car is indeed very original in many ways and i'd like to keep it that way as much as possible, but trusting it will start when I need it to is rather important, hence the quest for a more reliable solution (and I wouldn't mind if it was a bit more of a sporty drive ). In a way I'd like to just refurbish the current starter (if needed) and use the DEI wrapping on exhaust and starter if that reliably would solve the problem. (the one I have now came from Amazon here in Spain and is a generic chinese made product). It's not easy here in Spain to get parts and to find a shop that would be able to refurbish a starter is an impossibility. I would need to bring it with me to work in the USA (San Diego) and find a place there that could do it.

 

As someone who went down this road I have to say I think the starter is likely not the real issue here. I would look long and hard at the ground and power wire from the battery. I would likely replace the starter relay if anything or wrap the starter with a heat blanket but its likely not failing from the header pipes. I replaced my starter with an "S10" type which uses less current and delivers more starting torque and I wrapped mine in a heat blanket but in the end bot myself and my uncle with his 76 had the same issue and it was the old corroded wiring/ connections.

I purchased a cheap starter of this type off ebay after checking the reviews... That was 13 years ago and no issues since. https://www.ebay.com/itm/15415043812...BlBMUIimgdDNZA
I tried 2 of the other type of mini starters like you mentioned and had nothing but issues installing I even damaged my flywheel teeth with them before replacing with the type above that just bolted on and worked without the additional setup stress.

 

i think you could have someone get that pipe further away from that starter. . A local muffler shop may help here?
pics of entire exhaust helpful too. not sure if you still run CAT or true duals. probably biggest bang for buck would be dual exhaust L82 style and probably fix your heat issue.
NOTE- this thread walks thru my exhaust mod like yours . note the preheat valve was removed and recommend you do as well. since that post i put on a spacer. this allows pipes to sit a little lower away from starter, although mine was fine bolted tight for a while. Duals also eliminate one pipe by starter
https://www.corvetteforum.com/forums...79-4speed.html


should look like this depending on cat or not..



i recommend removing this

this is removed but put spacer in months later for proper pipe alignment as it puts it even further away from starter. note the transition from 2" pipe to 2.5 inches on the L82

 

Double layer aluminum heat shield.

Attaches to starter and protects the motor, solenoid and wiring.

Got that from Competition Products. Worked great on my other car. If you just get a "click" then you probably need one of these.

I run the Delco mini PMGR starter on my Corvette. Needs no brace or shield.

Leigh mentioned the ground connection.....THIS!

If you start easy when cold but it just cranks slowly when hot, make sure your ground cable is clean and tight. I had installed a knife style disconnect and it would not flow enough power when the engine was hot. Took the disconnect out and we start up just fine even when hot now. Going to switch to the **** style and see if it works better.

 

Thanks for all the detailed information. Very much appreciated. I'm a bit jealous now looking how tidy that all looks. Mine isn't anywhere near that (yet?). I think for now I'm going to try it with heat wrap around the starter and pipe. Next might be the solenoid as per your thread. All ground connections were cleaned up and checked. No issues there.
I do have the original pipe with cat as shown in these pictures. I did think about the true dual pipe solution but for now will have to put that on a back burner: Importing those into Spain will be rather costly. Based on experience with other, smaller items the cost can easily doulbe or triple with freight, taxes, clearance fees, etc. I also need to look into originality of the car. It is regisered as a 'historico' here and that comes, along with many other things, with the requirement that the car is original without significant modifications. A 'lab' does the research first and documents the car's tech specs. Now I doubt that the exhaust change would ever be detected here since they don't really see corvettes here at all at the technical inspections. If it's not mentioned in the report I'll keep the dual pipe option on the table, otherwise I'll have to forget about it.

 

Another likely cause can be the original battery cables, as many C3s ( and thousands of other GM vehicles) have aluminum cables. They corrode from the INSIDE with no clue on the exterior that they are not carrying proper voltage. Replacing them with 100% copper is your best upgrade.
Personally, I don't believe its the starter. These old Delco starters were built to handle that environment in many many different applications.
.
Thats what fixed my hot re-start issues.

 

💯 percent correct.

 

rtjsusa
Get a heat shield instead of wrapping the starter. I had one when I had headers. See the post by stingr69 above. I had to tweak the one I purchased but definitely provided shielding against the hot exhaust pipe.....

BUT I really think going to a mini-starter is the right answer. I would look for GM product so you can find a replacement easier later....that might be to your benefit being in your location.
see here and look at the comments section. some fellow says "swapped my starter on my ‘75 350 swapped Stingray with a ‘99 Tahoe Vortec 5.7 starter. Bolted right in, all the wiring was the same. It now cranks harder, and best of all, it’s smaller. Never going back."


and a link from the corvette ben with part numbers and whatnot.

 

Hi All, thanks for the input on this. I did check the voltage at various points and don't seem to have any significant voltage drop at the starter, grounds etc. I'll be picking up a heat shield and installing that first, see how the car does after that and the already installed exhaust wrap. if it continues, then I'll move towards a GM mini starter I guess.

 

I find it hard to believe those exhaust manifold temps (600) are normal.
I have headers, so I can't compare. However, each single header pipe runs from 350* - 400*.

Your manifold is so hot, I bet it glows in the dark. I have seen this issue before.
I believe what you are seeing is late valve timing. Basically, the IGN is firing closer to the exhaust stroke.
Maybe too much slop in the timing chain.
Maybe valve-lash set too tight on exhaust valves.
Or, valve seats in the head are burned resulting in leaking valves.

 

You wont necessarily have voltage drop. You will have a massive current drop however and thats whats needed here especially when hot. I learned this same thing the hard way on 2 hards now. If only a handfull of wire strands are conducting well on the connection ends where they attach you would still show full voltage. when I pulled mine off I found the copper was all corroded and green and very little metal to metal contact to pass current.

If you havent replaced the ground wire from your bat to frame I would do so / its easy and then look close at the terminal connections on your hot wire from bat to starter.

 

Although I think retarded ignition timing is a more likely scenario. Regardless, if originality is not a big concern, switch to the smaller gear reduction starter. I use the starter out of a 1996 full size chevy truck. Probably the same starter as was previously mentioned for the '99 Tahoe. Haven't had a problem since. As a bonus, it's also lighter than the original, and easier to install since it's smaller.

 

Same "S10 starter I mentioned as well... works great for me and I have side pipes very close to it.

 

Don't know if it is the same, but IF you do need a new starter you can also look into the LT1 starters for a C4 corvette. Direct swap and half the size and weight.
Since the car is newish to you? you might want to do a full tune up if not already done. Also bump up the idle timing to 10 degrees. While not optimal or set according to Lars' timing papers it will be better then what it currently is.
Are you sure the cat is fully flowing and not clogged at all? Might be another thing to look into.