Running hot after duraspark

[Twister]

Like the title says. I have an 85 B2 with the 2.8 and auto tranny. I did the duraspark converion about 5 months ago and every since it has ran hotter then before. Last summer it would hover around 195 and would barely hit anything above 200. Now it likes to sit at 205 and will not hesitate to get up to 215 and even 220.

I chased a running hot problem about 1 year ago and I replaced the radiator - t stat - fan clutch - and water pump.

How can I tell if I have an upper t stat? I have one that goes next to the water pump but on a parts truck I have it looked the same but had one in the upper part.

Sry if the grammer and spelling are off - I am posting this from my phone.

 

[kimcrwbr1]

There is a two piece thermostat housing that goes on the upper radiator hose from the intake manifold. I just put a plug in the bypass hose on the intake manifold and put the bypass on the stat housing. I believe mine came out of a 85 B-II and the guage rarely goes above half on scale and it used to run on the hot mark all the time. Make sure the timing is on 10 degrees btdc and use manifold vacuum for the advance then adjust the idle air for the highest vacuum or rpm. Mine starts right up after sitting a couple weeks and can put it in gear as soon as it starts without a hiccup. You will need to dial in the auto choke if it is working mine works perfect.

 

[Twister]

Will having the timing to far advanced cause it to run hotter? As of now it is set at 12*. This Monday i plan on messing with timing and getting the carb dialed in some more.

 

[Hahnsb2]

Retarded timing will actually cause it to run hotter. Is 12º enough timing for duraspark? Since I know on like an EFI 2.9, 10º with the SPOUT out is like 30º with the SPOUT back in. Does Duraspark use a SPOUT too or some kind of "base timing"?

 

[kimcrwbr1]

I would set it at 10 degrees and adjust the carb. Having the thermostat on the lower hose was always why mine ran hot. Check out all the bone yards you can for the two piece thermostat housing out of a 85 b-II with a/c you will know it when you see it, It has a 1 inch bypass fitting on the base along with heater nipple and the thermostat goes up front to the upper hose. I`m in CO right now at my cousins I will try and get you a pic of it when I get off from vacation I believe there are a couple pics here somewhere of the housing it is a rare item but works great.

 

[PetesPonies]

Too far advanced will in fact cause overheating. However, 12 degrees doesn't sound alike a problem. Could the mechanical or vacuum advance be stuck?? Also, the marks on the damper of a 2.8l are very difficult to read. Any chance you are reading them incorrectly?

 

[nightshift]

Duraspark

If all you did was convert to duraspark, I would bet you a cup of coffee that your timing is too retarded.

If this is duraspark II with a barometric pressure switch, disconnect the switch from the ignition module and install a jumper in its place.

Disconnect your vacuum advance and plug the vacuum line.

Make sure your idle speed is about 750-800 rpm in park.

Set your timing to 10 degrees BTDC. This is your "base" timing.

This is a good time to check your vacuum advance and centrifugal advance. With your timing light on, rev the engine a little and see if the timing advances. If your distributor has centrifugal advance (I'd be surprised if it didn't), you will see your timing advance. Next, connect a piece of vacuum hose to the vacuum advance. With the engine at idle, suck on the vacuum hose. You should hear your engine speed up. This indicates the vacuum advance is working.

Make sure your distributor hold-down is tight.

Shut down the engine. Reconnect your vacuum advance and baro switch, if equipped.

You may need to re-adjust your idle speed & air/fuel mixture when done, if your idle speed is different. It should be 600 rpm in drive (be careful!).

Invest in a Haynes Manual (#36070). Most auto parts stores will have them. Should be less than 20 bucks. It will be the best money you've spent in a long time.

That's all folks!

 

[Twister]

If all you did was convert to duraspark, I would bet you a cup of coffee that your timing is too retarded.

If this is duraspark II with a barometric pressure switch, disconnect the switch from the ignition module and install a jumper in its place.

Disconnect your vacuum advance and plug the vacuum line.

Make sure your idle speed is about 750-800 rpm in park.

Set your timing to 10 degrees BTDC. This is your "base" timing.

This is a good time to check your vacuum advance and centrifugal advance. With your timing light on, rev the engine a little and see if the timing advances. If your distributor has centrifugal advance (I'd be surprised if it didn't), you will see your timing advance. Next, connect a piece of vacuum hose to the vacuum advance. With the engine at idle, suck on the vacuum hose. You should hear your engine speed up. This indicates the vacuum advance is working.

Make sure your distributor hold-down is tight.

Shut down the engine. Reconnect your vacuum advance and baro switch, if equipped.

You may need to re-adjust your idle speed & air/fuel mixture when done, if your idle speed is different. It should be 600 rpm in drive (be careful!).

Invest in a Haynes Manual (#36070). Most auto parts stores will have them. Should be less than 20 bucks. It will be the best money you've spent in a long time.

That's all folks!

Well i haven't gotten to mess with my truck for a bit, it is my daily driver so it cant be down for very long. I am still having this issue, i know the t-stat will open because it will get to 195* then drop to 190* then just continue to climb. Me and my brother think maybe the transmission is causing it. My a4ld is dieing and wont shift before 3k on the tach, so every time i shift it has to be revved to 3k. I am swapping in a TK4 hopefully here in the next week, and i am hoping that helps.

Would shifting at such high rpm's cause it to run warm?

 

[kimcrwbr1]

Mine will creep up also on temp under a load and the tranny could give you that condition. Have you tried or do you have the advance on manifold vacuum or ported off the carb. With mine it is set to 10 dbtdc base and 20 degrees at an idle with the advance on manifold vac. turn the idle air jets out for the highest rpm or vacuum pressure and set the idle speed. Then check the idle air again until you get a nice smooth idle around 700 rpm then you can adjust the choke. Mine runs like crap with the advance ported from the carb at low speeds. It is my theory the idle air jets supplement the mains and if you are running too lean the cylinders are burning hotter hence more heat to dissipate. I also get alot better vacuum readings with the advance on manifold vac. Plus running it a little rich on the idle air means I dont have to push down on the pedal as far to get going adding up to better gas mileage. Try tuning it that way plug all the vacuum ports except the advance to the tree. Are you running a 2100-2150 carb did you cap the heater tube to the choke thermostat that is the threaded part on the housing that goes down at at angle toward the firewall. If it has the brass fitting use a 3/8 cap for refrigerant or find the right size plug. Just throwing out stuff to try you cannot hurt that engine doing so. The only way to hurt it would be to run too small of jets I am running #46s and the stock carb has #50s. Keep the timing at 10 degrees base all my attempts at different settings showed no improvment but using manifold vacuum made all the difference.

 

[Twister]

Mine will creep up also on temp under a load and the tranny could give you that condition. Have you tried or do you have the advance on manifold vacuum or ported off the carb. With mine it is set to 10 dbtdc base and 20 degrees at an idle with the advance on manifold vac. turn the idle air jets out for the highest rpm or vacuum pressure and set the idle speed. Then check the idle air again until you get a nice smooth idle around 700 rpm then you can adjust the choke. Mine runs like crap with the advance ported from the carb at low speeds. It is my theory the idle air jets supplement the mains and if you are running too lean the cylinders are burning hotter hence more heat to dissipate. I also get alot better vacuum readings with the advance on manifold vac. Plus running it a little rich on the idle air means I dont have to push down on the pedal as far to get going adding up to better gas mileage. Try tuning it that way plug all the vacuum ports except the advance to the tree. Are you running a 2100-2150 carb did you cap the heater tube to the choke thermostat that is the threaded part on the housing that goes down at at angle toward the firewall. If it has the brass fitting use a 3/8 cap for refrigerant or find the right size plug. Just throwing out stuff to try you cannot hurt that engine doing so. The only way to hurt it would be to run too small of jets I am running #46s and the stock carb has #50s. Keep the timing at 10 degrees base all my attempts at different settings showed no improvment but using manifold vacuum made all the difference.

It is running with the advance connected to the vacuum tree. I have it set at 12 btdc. I am running a 2100 and i don't think i have the heater tube blocked, never though of that. I rebuilt the carb a few months ago and i am pretty sure it had size 50 jets. Maybe ill try putting the advance tube on the side of the carb instead of the vacuum tree. I have Monday, Tuesday and Wednesday off so i will be messing with it then. Thanks, hopefully i can get this fixed.

 

[kimcrwbr1]

fixing the vacuum leak should help some sounds like mine before I put the thermostat on the intake manifold. It allways loomed around the top of the norm scale. As long as it is not overheating these engines are made to run hot. You may want to change the oil a little more often but I would focus on finding the thermostat housing for the intake that has the bypass nipple on it. It is a two piece housing and the bypass nipple out the side of the intake manifold just gets plugged. I cant say what year it came off but I believe it was a 85 B II with air conditioning. I am sure it will run cooler if you put the thermostat there and take the one out of the lower housing.

 

[84bluebronco2]

I am swapping in a TK4 hopefully here in the next week, and i am hoping that helps.

If you didn't swap the TK4 yet, think before you do. My 84 2.8 B2 had a TK4, and if you are worried about high RPM, don't swap it. The TK4 made it hard to exceed 55 without revving the hell out of my 2.8. I would have loved a TK5 or any of the FM series in that truck.

 

[84bluebronco2]

I am swapping in a TK4 hopefully here in the next week, and i am hoping that helps.

If you didn't swap the TK4 yet, think before you do. My 84 2.8 B2 had a TK4, and if you are worried about high RPM, don't swap it. The TK4 made it hard to exceed 55 without revving the hell out of my 2.8. I would have loved a TK5 or any of the FM series in that truck.

 

[Twister]

If you didn't swap the TK4 yet, think before you do. My 84 2.8 B2 had a TK4, and if you are worried about high RPM, don't swap it. The TK4 made it hard to exceed 55 without revving the hell out of my 2.8. I would have loved a TK5 or any of the FM series in that truck.

What do you mean? Its going to rev like crazy going highway speeds because it has not overdrive.

 

[kimcrwbr1]

http://img.photobucket.com/albums/v623/85_Ranger/Ranger water pump fun/Picture007.jpg?t=1274804662 This is what the two piece stat housing looks kike.

 

[84bluebronco2]

What do you mean? Its going to rev like crazy going highway speeds because it has not overdrive.

I'm just saying that unless you only plan to only use your B2 in low speed situations, the TK4 from my experience would not be a desirable transmission. I'll give it points for being a tough little bugger, but gear ratios wise, I was not pleased.

 

[kimcrwbr1]

I wish I had O/D after 60 mph with the 3 speed auto it raps out pretty good.

 

[Twister]

I'm just saying that unless you only plan to only use your B2 in low speed situations, the TK4 from my experience would not be a desirable transmission. I'll give it points for being a tough little bugger, but gear ratios wise, I was not pleased.

Well with my B2 I do about 90% city and about 10% highway - so it should be fine. Anything is better then the worn out piece of crap a4ld I have now.