85 blazer 305 engine starter problem

ubee · 03-20-2008, 05:33 PM

have 1985 blazer 305 eng. guy says heat shield missing from starter. when hot wont start. spray with hose and it starts right up. anybody ever have this problem .was heat shield just tin ? thanks jb

75K30 · 03-20-2008, 06:56 PM

Heat shield is just tin, and just about every person with a chevy engine has encountered this "heat soak" symptom.
The heat shield helps, and a new starter is probably less likely to have this problem.
The best results are with a smaller diameter starter (mini starter, gear reduction type) which places the starter further away from the exhaust and is less likely to encounter "heat soak" symptoms.
There is yet another fix, and it requires a ford style solenoid located up on the firewall, or inner fender. You remove the ingintion lead from the chevy starter and wire it to the ford style. This will activate the solenoid. Then remove the 12v cable from the starter and install it on the common side of the solenoid. Next install a new cable from the switched leg of the solenoid to the chevy solenoid where the old cable was installed. A jumper (preferably solid copper, but a wire jumper will work) needs to be placed between the 12v supply (main post) and the small post that was originally used to energize the coil. This will directly apply voltage to the old solenoid when the key is turned and the new ford style solenoid is activated.
Guarantee you will never see a heat soak problem again.
I no longer run any stock chevy style solenoids on any chevy starters. I use this method and modification for all of my chevy staters, including my high compression big blocks with large diameter headers, and I never have a problem with the dreaded heat soak.
Hope that makes sense.

dawright_1988 · 03-20-2008, 08:58 PM

My dad's old blazer had the same problem, believe it or not. I know it sounds silly, but the dinky little tin heat shield actually helps a lot. It's all about the heat-sync idea. It doesn't really insulate, but it gives a different rout for the heat to travel. Kind of like those aluminum riges that you see on the back of computers or amplifiers or something. That's all those things do is just give a new route for the heat and pull it away from the vital component.

crabtruck · 03-21-2008, 02:34 AM

This tin may be for a heat shield to stop the starter from being a heat sink, but it clearly shows how bad that heat is for the poor starter. IMO if you're going to work on it, mod it as 75 said, so you never have to come back to that again.

87c10slammer · 03-22-2008, 07:54 AM

if you dotn want to do all that work they sell starter heat sheilds that replace your tin one and i have never had a problem on any of mine after i put it on. its just some insolation cloth and a metal foil around it. it just gets clamped on. go to your local autoparts store and thell know what im talkin about

03-20-2008, 05:33 PM	#1
ubee Junior Member Join Date: May 2007 Posts: 8	85 blazer 305 engine starter problem have 1985 blazer 305 eng. guy says heat shield missing from starter. when hot wont start. spray with hose and it starts right up. anybody ever have this problem .was heat shield just tin ? thanks jb

03-20-2008, 08:58 PM	#3
dawright_1988 Senior Member Join Date: Apr 2007 Location: Adrian, MI. Posts: 146	My dad's old blazer had the same problem, believe it or not. I know it sounds silly, but the dinky little tin heat shield actually helps a lot. It's all about the heat-sync idea. It doesn't really insulate, but it gives a different rout for the heat to travel. Kind of like those aluminum riges that you see on the back of computers or amplifiers or something. That's all those things do is just give a new route for the heat and pull it away from the vital component. __________________ "You can polish a piece of junk all you want, but in the end, all you're left with is shiny junk."

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
99 Ford F150XL 4.2L 6 Suggestions on removing starter from engine compartment...	mlongue1	Ford Truck Forum	3	12-05-2007 03:15 PM
93 blazer 4wd problem	Hayden	Chevy Truck Forum	6	06-11-2007 01:27 PM
Is It A Battery, Solenoid or Starter Problem?	NH_Bert	GMC Truck Forum	3	05-24-2007 02:09 AM
Starter problem, need help.	MadMazda	Mazda Truck Forum	6	01-21-2007 09:52 AM
95 S10 Blazer Problem	4x4s1088	Chevy Truck Forum	20	07-31-2006 09:38 AM

03-20-2008, 06:56 PM	#2
75K30 Senior Member Join Date: Jul 2006 Posts: 2,627	Heat shield is just tin, and just about every person with a chevy engine has encountered this "heat soak" symptom. The heat shield helps, and a new starter is probably less likely to have this problem. The best results are with a smaller diameter starter (mini starter, gear reduction type) which places the starter further away from the exhaust and is less likely to encounter "heat soak" symptoms. There is yet another fix, and it requires a ford style solenoid located up on the firewall, or inner fender. You remove the ingintion lead from the chevy starter and wire it to the ford style. This will activate the solenoid. Then remove the 12v cable from the starter and install it on the common side of the solenoid. Next install a new cable from the switched leg of the solenoid to the chevy solenoid where the old cable was installed. A jumper (preferably solid copper, but a wire jumper will work) needs to be placed between the 12v supply (main post) and the small post that was originally used to energize the coil. This will directly apply voltage to the old solenoid when the key is turned and the new ford style solenoid is activated. Guarantee you will never see a heat soak problem again. I no longer run any stock chevy style solenoids on any chevy starters. I use this method and modification for all of my chevy staters, including my high compression big blocks with large diameter headers, and I never have a problem with the dreaded heat soak. Hope that makes sense.

03-21-2008, 02:34 AM	#4
crabtruck Senior Member Join Date: Jul 2007 Posts: 1,474	This tin may be for a heat shield to stop the starter from being a heat sink, but it clearly shows how bad that heat is for the poor starter. IMO if you're going to work on it, mod it as 75 said, so you never have to come back to that again.

03-22-2008, 07:54 AM	#5
87c10slammer Banned Join Date: Mar 2008 Location: levittown pa Posts: 2,197	if you dotn want to do all that work they sell starter heat sheilds that replace your tin one and i have never had a problem on any of mine after i put it on. its just some insolation cloth and a metal foil around it. it just gets clamped on. go to your local autoparts store and thell know what im talkin about