Heat problem 96

[Laimon]

I have a 2.5L Stratus, I have hot engine problem when engaging air conditioner. engine heats up to H and cooling liquid boils off.
But when cruising around 60m/h with Air conditioner ON , engine is cool !

Otherwise engine is cool all the time without air conditioner.

fans, water pump and thermostat were replaced, problem remains.

any ideas?

[StandOnCliff]

Sounds like the fans are not functioning. Going down the road you won't use the fans. Air goes through fast enough to keep it cool enough that they are not needed. Check your fan relays,fuses and temperature switch. You should have a low speed and high speed relay. The vehicles fans should go to high speed when A/C is engaged or when low speed isn't good enough. If they seem to be working fine,check your radiator for buildup and flush as needed.

[Laimon]

I replaced fans and modified them to work always on high speed. I did a flush last month to my radiator. you think fans are not fast enough ?

[StandOnCliff]

If they are truly running on high then they should be fast enough to work. Have you tried blowing out,with an air hose, through the radiator to make sure it isn't clogged with leaves,grass and such? Any chance pulleys running with the A/C unit are freezing up? Not sure what temperature thermostat you went with but try lower like a 180 versuses a 195. The other thing could be a bad head gasket,but it doesn't make sense it only shows up with A/C engaged.

[Laimon]

if it is a bad or blown head gasket it would heat up always even without A/C . Ofcourse I tried cleaning up my raidiator from dust, replaced coolent as specified in user manual. but could you explain more about the pulleys if they are freezing? you think that compressor is hard to rotat and being a big load on engine?I don't hear any noise coming from compressor ..

[StandOnCliff]

The air conditioner does put an extra load on the engine,thats why you get worse gas mileage. Pulling the belt off and making sure the tensioner pulley and such are rotating freely is what I was saying. Make sure it doesn't have additional drag. I agree on not being a head gasket,but it definately has something not right. If the radiator is flushed entirely and cooling fins clean with a new pump and thermostat and the fans running on high all the time it shouldn't have a problem. Did it have alot of build up in the radiator,maybe try another flush if it did. Lower temperature thermostats are usually a good quick fix too.

[Laimon]

I will double check on belt today, I hope they are the reason for that load. Radiator was little dirty when i flushed. I think radiator is ok, just something wrong with load. perhaps compressor is too heavy and needs service?

[Laimon]

Belt is OK, and pulleys are moving freely, I have removed thermostat for good ! but problem remains. The problem could be a clogged A/C compressor, but it would make some noise.
I noticed another problem today, when pressing gas paddle fast, engine doesn't act quicky, and i hear few ' bangs' before responding. could be throttle position sensor?

[StandOnCliff]

That could be a throttle position sensor but really sounds more like maybe a timing issue. Timing being off would cause it to run warm also and bang when you mash the throttle. If you have an analog ohm meter you can check the TPS(digital doesn't work right). Connect one end in center prong of the TPS other end in either sides. Measuring resistance,the needle should move slowly up or down,depending on which outer prong your connected to,as you slowly increase or decrease throttle. Any spikes or jitters you see with the needle means it's bad. It should move fluently with the movement of the throttle.Even if the TPS was bad it wouldn't cause it to overheat. With no thermostat, it should never get off of cold. This is more reason to look for clogging issues,timing issues or head gasket as a last resort.I only mention the head gasket because if it is just starting to go the extra load might do this. If it continues to worsen I would be looking into it.Personally I've never herd of a compressor getting too heavy,it just freezes and don't work anymore if it's a full system. Try topping it off with freon that has lube in it. The compressor would make a squealing noise before getting to the point of too much stress for the engine. Being too low in freon would also show evidence by not being as cold as it used to be out of the vents.

[Laimon]

I have checked timing belt, it is OK , throttle position sensor seems OK too, with multimeter, it gives high resistance between pin 1 and 3, when moving throttle, resistance become lower. heat problem strated to be even without A/C .
My dealer says, as long as i don't have water in my oil or oil in my water then head gasket is OK , I didnt buy that ! ..it seems to be a head gasket issue starting. shall i remove radiator for total inspection or start with big dirty job changing head gasket?

[StandOnCliff]

Dealer is wrong. Some head gaskets blow between the piston and a water port which just makes it boil over all the time and never mixes oil and water.Personally I would start digging into the nitty gritty head gasket job. It's never really a waist of time,since head gaskets failing in Chrysler's is all too common.Remember when doing it,clean,clean and then clean again. One speck of dirt or old gasket left behind will blow it out again. If you don't have a Haynes manual for your vehicle,it is highly suggested to get one for this job or to go to the local library.Mostly for the correct torque procedure.Aluminum heads should never be torqued right to spec they need done in steps and a sequence as the book will tell you.A burnt metal ring on the head gasket,usually around the piston,will let you know it was the problem.It getting worse is a definate sign. A temporary fix can be to use silver solder or any other type stop leak,but I don't like using it personally.

[Laimon]

Yes, dealer is wrong , I know that it is something wrong with head gasket. I do have Haynes manual in pdf, i shall print it. I'm starting on friday, seems to be all weekend work.
tell me please what is stop leak ? u add it to water or to your oil ? is it effective?

[Laimon]

One more thing, do i have to take head somewhere to workshop to check for roughness?

[StandOnCliff]

Stop leak goes into your radiator. There is a brand called silver solder that seems to work better then the rest. It has fine particles that block holes off.It works nice with small radiator leaks and is just a temporary,if at all ,fix for a head gasket.Black pepper can work too,yes,household black pepper. I personally don't like to use it,just delays the inevitable and possibly clogging the system. It is always highly suggested to take the head in and have it checked for flatness and pressure tested. It is also suggested to replace the head bolts along with the head gasket.

[StandOnCliff]

If you do decide to try a stop leak temporary fix. I suggest when you do the head gasket to flush your cooling system entirely.

[Laimon]

I don't like to use stop leak, but i would try it only to make sure that my problem is with gasket. anyway i used it once and blocked my flow system.
Let's assume it is really a blown head gasket, I should have lose of performance at least. or if you say that compression of pistons are leaking into water and heating it up to boil. that means at least i should have a smell of burn or something into my coolent, right?
Check of flatness is a must, if my engine's head is not flat, I would have a mess into my radiator as oil would leak. anyway i will check it just to make sure everything is ok.

[StandOnCliff]

Stop leak blocking the flow is why I don't use it either. Without the proper testing tools it is all speculation. A compression test and a coolant pressure tester would be able to tell you for sure. As for a burning smell in the coolant that won't happen as water isn't flammable,might be able to get a wiff of raw fuel smell though or an oily film floating.The loss of performance would be so minimal that unless it was hooked up to an analyzer you wouldn't notice.If it was bad enough to show performance loss you would have definate signs,white exhaust and such.The pistons run over 100 pounds of compression and the cooling system runs around 12 pounds of pressure.If you start pushing 100 pounds into a system only designed for 12 pounds,it isn't boiling out it is being blown out until there isn't enough to cool the engine,then it will begin overheating. Pulling spark plugs and looking at the tips can also help in diagnosing.All the spark plugs should look the same. I had a 70 Javelin that I couldn't keep water in it for 3 miles before. It just kept blowing the water right out. It would be blowing out for ten minutes after I shut it off.I seen no white smoke coming out of the exhaust,no water in the oil and it all started with it just overheating every once in a while and kept getting worse until this point. If we take into consideration of a brand new water pump,clean coolant passages,no thermostat and fans are running what else could be wrong and causing it to overheat.The heater core would have nothing to do with the problem. The only other item to try before doing anything would be to try a brand new radiator cap. If it's getting worse,I would doubt it would be the problem though.Caps when they go bad just keep letting water out for days before it runs so low in coolant it finally overheats and doesn't overheat until then,unless of course the rubber in the cap is totally gone.Aluminum heads like to warp from getting heat where heat wasn't designed to be.They can seem fine until you pull them and actually be worse when reinstalled if not checked. Them being bolted in place don't allow them to show they are warped.I used to work in a heat treating facility and we seen this many times.To try to heat treat a crankshaft without a holding fixture,it would warp over .150,in a fixture that was straight and true it would still warp .030,but be straight and true while still bolted in the fixture. Basically with it off is the time to check, just to make sure your putting a good head back on.The pressure testing is to make sure it isn't a cracked head instead of a burnt gasket.It would suck to put it all back together and still have the same problem and find out later it was a cracked head and now it needs to come back apart. A little extra now can save later.

[StandOnCliff]

I just thought of another thing it could be and definately would cause it to overheat. If it is like an Intrepid there is a bleeder valve near the thermostat housing.It must be opened until nothing but coolant is coming out of it while filling it or it will have air pockets. I even,when filling them,will start it with this bleeder valve open until nothing but coolant comes out.

[Laimon]

I have checked the manual, there is nothing like bleeding valve. I also have checked my coolent for oil films, I must say it is very very clean. my coolent level is always the same which determines no lose.
I will remove my radiator for total inspection, perhaps there is a clogging.
If radiator is OK, then I will start digging engine for gasket.

[StandOnCliff]

If you bought this vehicle and it has had this problem since you've owned it. When you have the radiator out look for repairs done to the radiator. The bottom cooling passages like to rot out. Repairing consists of cutting those cores out and soldering them shut on the tank sides. If enough of these passages were repaired it would make it to where not enough cooling is being done in the radiator. The only fix for that is a new radiator. If it does have a bleeder valve it would be right at the thermostat housing. It opens with a 10 mm wrench or socket. Its hard to miss if you have one.

[Laimon]

I must say you are 100% right, it is a head gasket ! ..I have consumed alot of time inspecting the radiator for potential blockages or clogging. my radiator is very clean.
I will start replacing head gasket soon, please could you provide me some online shopping for spare parts? my local dealer provides parts on order, means i must wait few days after ordering and seems to be too expensive.
If you could please advise if there is anything i must replace while digging to head gasket ?

[StandOnCliff]

The best way to get everything you need the first time would be to order a Head Set. It contains every gasket you will need. Intake manifold,exhaust,head gaskets,valve covers and such it is Part Number: HS9037PT(it's $204). You might want to get some silicone also,sensor safe type. Antifreeze,oil,oil filter are also needed. I do my shopping for auto parts here http://www.partsamerica.com/Default.aspx and http://www.autozone.com/home.htm and http://www.napaonline.com/default.aspxthere are others,but they seem fair price. The Parts America is actually now called Advance Auto locally. If those,you don't wish to use,then you can find any others here http://www.indexoftheweb.com/

[Laimon]

if there is a problem with head flatness, It must be repaired right? and then we must use double head gaskets ?

[StandOnCliff]

The machine shop,if it is warped, will use a mill to flatten it again.They shave off of the bottom the required amount. They know the specs on these heads and will not mill out too much. They'll inform you that the head is shot if it is that bad. Never use more then one gasket per head. Clean,clean and then clean again the block. When you take the heads into the shop ask them how much for glass bead cleaning so you don't need to clean them up also. It cost me about $100 for them to clean them,pressure check them and check for flatness. My flatness was within spec,so it would of cost about $50 more for them to do if needed. All machine shops are not created the same,so call all you can for pricing. I can't express more on cleaning it is the one thing that makes it a waist of time if you don't. Head gaskets are not reusable either,so if it has to come back apart that $200 for gaskets need bought again.

[StandOnCliff]

Just another quick note to let you know. My heads were barely in spec and my engine didn't even blow a head gasket. I was replacing my engine with another good running one and replaced everything while it was out so it had no oil leaks or head gasket issues later. Just so you realize,they probably will need done,so basically plan on it as an expense and if not your happier.Timing belt or chain should be done too,while it's out,if your engine requires it to be removed for the heads. You already did the water pump or I would suggest that too.

[Laimon]

I searched the service manual for spec, i just can't find them. but i found in cooling section for troubleshooting and diagnosing, that it is normal for engine to overheat when A/C is on in a slow trafic flow. especially when ambient temprature is high.
I really don't know for sure now if I have to dig to my head gaskets ? or shall i modify my A/C system to make less load on engine, or replace my fan by a powerful electrical fans? really i'm confused now ..

[Laimon]

Ok I would like to review the symptoms.
My antifreeze is clean, no smell of gasoline or anything unusual. I have no loss in coolent.
When starting car in the morning, I can drive for 1-2 hours in trafic jam with A/C on, and temp gauge does not exceed a qaurter.
after 2 hours gauge rise to half and coolent starts to boil off into recovery reservoir.
when disengaging A/C , temprature drops to quarter.

When cruising with A/C around 40-55 mph , gauge is within green zone.

I absolutly have no idea what to do now, I'm afraid to dig to head gaskets and find out nothing is wrong, will be hell a waist of money and time ..

[StandOnCliff]

Well if the manuals right,thats a dumb design. Ambient temperature being high and slow in traffic (or stopped),is when I tend to use A/C the most...LOL. Modifying the A/C system isn't probably going to help. Going to more fan blades per fan or bigger fans themselves will. If thats what the manuals saying,I would go to the junkyard and look for a fan assembly thats compatible and bigger. Even if it doesn't solve your problem now,it'll definately help later. More air flow never hurts.

[Laimon]

Yes in section 7 ( cooling ) for solution of engine overheating it says it is normal in slow trafic, or if something towed or climing a hill. we should switch off A/C.
This is really dumb, but to overheat till H and always. I mean I see alot of dodges around here and all are using their A/C with no problem .
I'm worried if I go for bigger blades fan and neglect having head problem then it will be worse and I'll have later to replace heads.

[Laimon]

I finally removed head last night, head gasket looked OK but when testing head for flatness, test failed.. head was not flat by 0.1mm at least. it is twisted.
could be the reason for excessive heat ?

[StandOnCliff]

To check your gasket look for a burned up area on the rings that goes around the cylinders or a piece of the ring missing. Also look for evidence of coolant leakage around the water ports on the gasket.Basically look for anything out of the ordinary,comparing results to the other cylinders on that same gasket.Check all your coolant passages going into the block for buildup also.If it was just starting to go it will be hard to see with very little burned off. If it didn't blow a gasket,it being a little warped wasn't causing it to overheat.I wouldn't put it back together until it was milled flat though.

[Laimon]

No burns around the O ring for any cylinder head. there were some blockages, I found a big ring of silicon in one of coolent passege. I took head for mill this morning, they say they must mill @ 0.4mm , They also said that this is really commen for dodge to overheat becouse of head flatness, they said it was just the begining.
I'm putting back all togather tonight, let's hope everything will be alright.

[Laimon]

Ok, I assembled engine back ..engine is top !! ..no heat problem anymore.
thanks all for help ..