Welcome to www.JeepStrokers.com!!
Not yet a registered user? You are required to Register before you can post within this topic.

Troubleshooting Advice on overheating with new stoker

Performance mods and Advanced Stroker discussion.
Post Reply
Jmfelty
Posts: 5
Joined: July 6th, 2019, 10:12 pm
Stroker Displacement: 4.7
Vehicle Year: 1998
Vehicle Make: Jeep
Vehicle Model: Cherokee

Troubleshooting Advice on overheating with new stoker

Post by Jmfelty » July 8th, 2019, 4:05 pm

Stroker experts,

Do any of you have sage advice for troubleshooting overheating on a new stroker build. The stroker was build with 1998 block and BnB parts from Russ P. Including pistons, rods, crank, ported head, cam shaft, port matched intake, with .030 over on the cylinders, and a .010 deck on the block for a stated compression of about 9.3. The builder used a racing head gasket with stainless steel layers at stock thickness that matched the .030 over bore. The exhaust is Banks headers with a full two inch down tube to a cat back banks exhaust. The computer is stock. The cat is out of the Jeep while I break in the engine.

I have new parts including: mishimoto aluminum radiator, silicone hoses, flow cooler water pump, new thermostat and housing, new heavy duty fan clutch. Ac condenser, and a plate transmission oil cooler mounted on the passenger side in front of the mechanical fan. The electrical fan is working and pulling decent amounts of air. I have a new temp sensing gage that is working and giving realistic readings. Jeep is on 35” tires with 4.56 gears, and now which or airflow obstructions.

I have driven it about 200 miles after the build and I know it is hot in Phoenix right now, but I am fearful to take my eyes off the temp gage. A couple of times it has gotten into the 240 degree range and flashed the engine light before I turned the cab heater on to cool it back down. Without the AC running and keeping steady air flow it will hold under 220, but any stop light or heavy throttle load will raise the temperature (Out side air in the 105 range). I drove it this morning with the temperature in the mid seventies, and the temp hovered at 205, and climbed at every stop light). I am worried about overheating the silly thing during break-in and how to troubleshoot. I have ordered a wide band sensor and will look to have the JTEC computer tuned, but I am currently pulling my hair out. Prior to the stroker build the engine never had overheating issues and could drive anywhere without concern with stock radiator and parts. The only air flow change was adding the transmission cooler in front of the radiator when the new parts were installed. No pinging detected, and I am running premium fuel. No other drivability issues and it pulls better that the 4.0 (But not as strong as expected) Any advice on troubleshooting prior to putting the wideband sensor in the vehicle? Any benefit in relocating the transmission cooler to the other side of the engine?

Thanks,

John

User avatar
SkylinesSuck
Donator
Donator
Posts: 490
Joined: February 14th, 2009, 11:11 pm
Stroker Displacement: 4.6L
Vehicle Year: 1998
Vehicle Make: Jeep
Vehicle Model: Wrangler
Location: Northern VA

Re: Troubleshooting Advice on overheating with new stoker

Post by SkylinesSuck » July 8th, 2019, 9:40 pm

Either a timing issue or more likely still air bubbles in the coolant system. What injectors are you running?

User avatar
Cheromaniac
Senior Member
Senior Member
Posts: 2740
Joined: March 8th, 2008, 12:58 pm
Stroker Displacement: 4563cc
Vehicle Year: 1992
Vehicle Make: Jeep
Vehicle Model: Cherokee
Location: Cyprus
Contact:

Re: Troubleshooting Advice on overheating with new stoker

Post by Cheromaniac » July 8th, 2019, 10:12 pm

There will be more internal engine friction during the break-in so that may be a contributory factor in the engine running hot. It doesn't sound like there's any problem with the cooling system itself, especially if there's no coolant leak, and ignition timing is controlled by the PCM, so I think there's a fair chance that the engine's running lean.
Which injectors did you use?
1992 XJ 4.6 Stroker - 5MT - Sold :cry: Stroker build-up, Stroker "recipes"
2006 Mustang GT - 5MT - Midlife crisis car :D with Mods

Jmfelty
Posts: 5
Joined: July 6th, 2019, 10:12 pm
Stroker Displacement: 4.7
Vehicle Year: 1998
Vehicle Make: Jeep
Vehicle Model: Cherokee

Re: Troubleshooting Advice on overheating with new stoker

Post by Jmfelty » July 8th, 2019, 10:45 pm

The injectors are 27lb Bosch - The Cam is a 68-235-4

My engine builder thought it would run hot with that cam based on his experience building engines in Phoenix. His advice was to try a dual radiator setup to get some additional cooling.

My guess is that it is running lean with the stock tune, but I won’t know until I have a wideband installed.

Jmfelty
Posts: 5
Joined: July 6th, 2019, 10:12 pm
Stroker Displacement: 4.7
Vehicle Year: 1998
Vehicle Make: Jeep
Vehicle Model: Cherokee

Re: Troubleshooting Advice on overheating with new stoker

Post by Jmfelty » July 8th, 2019, 10:48 pm

There is no external coolant leaks and the overflow bottle has been keeping a constant level when cooled.

Jmfelty
Posts: 5
Joined: July 6th, 2019, 10:12 pm
Stroker Displacement: 4.7
Vehicle Year: 1998
Vehicle Make: Jeep
Vehicle Model: Cherokee

Re: Troubleshooting Advice on overheating with new stoker

Post by Jmfelty » July 9th, 2019, 11:41 pm

I removed the external transmission cooler and got the temps to stabilize. It is still running hotter that I would like, but much more manageable. It will hold at 215 idling with out the ac, but climbs with it on. I ran down the freeway at 75mph and the temp held near 228 with the ac on as reported by the scan tool. Still waiting for a wideband.

User avatar
Cheromaniac
Senior Member
Senior Member
Posts: 2740
Joined: March 8th, 2008, 12:58 pm
Stroker Displacement: 4563cc
Vehicle Year: 1992
Vehicle Make: Jeep
Vehicle Model: Cherokee
Location: Cyprus
Contact:

Re: Troubleshooting Advice on overheating with new stoker

Post by Cheromaniac » July 10th, 2019, 1:02 am

Jmfelty wrote:
July 8th, 2019, 10:45 pm
The injectors are 27lb Bosch - The Cam is a 68-235-4
In that case I think it's less likely that the engine's running lean, and more likely that it just needs more break-in time.

User avatar
SkylinesSuck
Donator
Donator
Posts: 490
Joined: February 14th, 2009, 11:11 pm
Stroker Displacement: 4.6L
Vehicle Year: 1998
Vehicle Make: Jeep
Vehicle Model: Wrangler
Location: Northern VA

Re: Troubleshooting Advice on overheating with new stoker

Post by SkylinesSuck » July 10th, 2019, 7:24 pm

How much effort did you put into bleeding air out of the coolant?

User avatar
Cheromaniac
Senior Member
Senior Member
Posts: 2740
Joined: March 8th, 2008, 12:58 pm
Stroker Displacement: 4563cc
Vehicle Year: 1992
Vehicle Make: Jeep
Vehicle Model: Cherokee
Location: Cyprus
Contact:

Re: Troubleshooting Advice on overheating with new stoker

Post by Cheromaniac » July 11th, 2019, 8:56 am

In my experience the Jeep 4.0 cooling system does a pretty good job of bleeding itself. That said, it wouldn't hurt to park the Jeep nose up and start the engine from cold with the radiator cap off. Any air would then come out, the coolant level would drop, and you'd then need to just top it up again.

Jmfelty
Posts: 5
Joined: July 6th, 2019, 10:12 pm
Stroker Displacement: 4.7
Vehicle Year: 1998
Vehicle Make: Jeep
Vehicle Model: Cherokee

Re: Troubleshooting Advice on overheating with new stoker

Post by Jmfelty » July 11th, 2019, 11:18 am

I will try to do some additional bleeding, but I did check the level at the radiator cap and it was full after a couple hundred miles of driving. The coolant level in the fill bottle is consistent. I thought the later model Cherokee’s did not have too much trouble with burping themselves through the coolant overflow bottle. I did get a aux radiator from an Audi S4 and will try to mount and tie into the heater lines. It is about 8 x 10 inches and I think i have a couple of spots that could work. That aux radiator has 3/4 inch outlets and no radiator cap. I am waiting on the rest of the parts to install. Based on my observations I am not too far from keeping it cool.

astjp2
I think I'll order a "tab"
I think I'll order a "tab"
Posts: 45
Joined: September 11th, 2008, 8:50 am
Stroker Displacement: 4.7
Vehicle Year: 1994
Vehicle Make: Jeep
Vehicle Model: Wrangler

Re: Troubleshooting Advice on overheating with new stoker

Post by astjp2 » July 22nd, 2019, 9:33 pm

My stroker has ran hot since the day I built it, but I was not able to control the timing in a 94 YJ like I want to. I dont think anyone is able to reprogram the PCM so I am stuck for now, but it has been only 15 years since I built it.

Post Reply

Who is online

Users browsing this forum: No registered users and 4 guests