Questions about V6 IROC Daytona

[lsm71]

Hi all-

My name is Scott and I recently bought my son Patrick a V6 IROC Daytona for his first car. The car is in nice shape cosmetically but needs a little work under the hood. The main issue is a coolant leak, which looks to me as if it's leaking at the block where the the lower radiator hose fitting is pressed into the block. I'm fairly confident that I can fix it, my problem is I don't know what it's called or how it's attached and I'd like to do some research before just ripping into it.

Here's a few pictures of the car. It's a nice car and he's excited to be bringing it back to life. I'm sure we'll both be spending plenty of time here on the forum.

http://img.tapatalk.com/d/14/05/12/ysedy5y7.jpghttp://img.tapatalk.com/d/14/05/12/yreby3ut.jpg

[A.J.]

Pictures of the coolant leak would be more useful than pictures of the exterior, as nice as the exterior is Most of us here work on the four cylinders and are not familiar with the V-6. I'm a professional auto technician and I can't tell you the last time I worked on one. So does the lower hose connect at the front or back of the engine?

Depending on where the leak is (please post pics) you have one of two problems. 1) If it's on the front of the engine it could be the water pump. Not a big deal but the timing belt drives it. 2) If it's coming off the back of the block, it could be the "coolant tube" that runs between the left and right cylinder banks which MIGHT require you to remove the intake to get to the o-ring that seals that pipe. I can't remember if it's necessary to remove the intake or not.

[Vigo]

On the 3.0 v6 the lower radiator hose connects to a long pipe that goes from the back of the water pump (at the front of the engine), the length of the valley of the engine, and comes out right at the top of the bellhousing at the back of the engine. That pipe has a big o-ring that seals into the back of the water pump housing and is held on by the top two bellhousing bolts of the transmission.

It's semi-common for them to corrode and spring leaks. I would definitely try to get eyes on the actual leaking spot before taking the pipe out if at all possible. You can still get replacement pipes (or used ones from the junkyard) but the risk you take in replacing the entire pipe is that you won't be able to clean up the water pump housing sealing surface without taking the entire intake manifold off the motor, and without doing that all you can do is stab the new pipe in there with a good o-ring and some anaerobic sealant or silicone and just pray. At least, this is how i remember it.

So definitely verify that the pipe itself has a hole before disturbing it.

[lsm71]

I'll try to get some pics of the leak tonight. The leak point is at the rear (drivers side) of the engine. I believe the "coolant tube" has hole'd through right where the tube meets the block. The car has 128K in it so I'm thinking it would prob be best to replace the water pump while I have it torn down....

[c2xejk]

To replace those tubes (two sections) you do NOT need to pull the water pump. However, if you are replacing the water pump, I would recommend doing the timing belt too. (Get a Timing Belt Component kit w/water pump. I would recommend a kit with a housing.)

RockAuto.com has the pipes, but they are listed in the 'Heat and Air Conditioning" section under 'Heater Hose Assembly'

On the O-rings, be sure to put some dish soap on them to lube them so the slide easily and don't tear.

[Reaper1]

The later 3.0's had the multi-piece coolant tube. I've seen 2-piece and 3-piece depending on the vehicle (like I said, these are later versions). I have seen them spring leaks where the hose is clamped onto the tube. As the others have mentioned, the most common place for failure is the o-ring that seals the tube to the water pump housing.

If you don't know if/when the timing belt was replaced, it might be a good idea, and while you're in there, do the water pump as well (you should always do these 2 together). It's really not that hard of a job. The engine is non-interference, so you don't have to worry about valves meeting pistons.

As for removing the tube you may have to take out 1 or 2 bellhousing bolts if there is a bracket holding the end of the tube. I want to say that after that you should be able to snake it out. you might have to play "Chinese puzzle", but I think it's possible.

[Ondonti]

I have gone through these forever owning 3x 3.0's and using a lot of different engines.

Most recent one I put a new waterpump on, traded for a less corroded block cross pipe, new O rings, lubed them up with soap....and then the next day the lower hose popped a leak right next to the spot yours is leaking.

The leaks on the drivers side have a lot of possibilities but if its just dripping down the transmission, its probably the O rings leaking. Sometimes the entire valley of the block can fill up from either the passenger side water pump O ring or the driver side O ring or both. You also change out the bypass hose and make sure those mating surfaces are in good condition.

I bought a bunch of new pipes but I am too cheap/hoarder to actually use them... BTW when I bought the new lower hose, I bought 2 and one of them was the wrong one. Called and they sent me another. That is the first time I have replaced a lower hose in the 13 years I have worked on these. Normally, its just O ring failures. You also have to be careful not to chew up new O rings by forcing on the water pump when you really don't have it properly aligned with the crossover pipe. Some water pumps don't have a bevel on their mating surface so you need to grind one in. I buy complete pumps now because they are nearly the same price and that part of the system corrodes too. Replacing half the pump and reusing a bad old housing is a thumbs down from the labor side of redoing things if it starts leaking.

[lsm71]

Here's a few pics of what I'm working with...

http://img.tapatalk.com/d/14/05/16/5ymajega.jpg

http://img.tapatalk.com/d/14/05/16/uguhe9an.jpg

I haven't been able to find a Repair Manual locally but did I order the parts from RockAuto today per all your suggestions. Hopefully this isn't too bad of a job. Thanks

[lsm71]

Definitely a bad o-ring... Looks like someone tried to make it seal with some black RTV which leaked and rusted the flange face of the rear tube. I'm sure the other section of tube is shot as well...

[lsm71]

I know looks can be deceiving but this belt looks pretty new to me...plus there's a few broken clips in the area which tells me the timing covers have been off before. What do you guys think?

http://img.tapatalk.com/d/14/05/16/hege5yne.jpg

[Vigo]

These motors are non-interference anyway, so if you're hard up for $20, leave it be. But if you're going to take it off to replace the water pump, you might as well spend the extra and get a new belt. It's cheaper than a tow bill if the reused one ends up slipping.

[Reaper1]

The outside edge looks like it has been rubbing on something.

I find it interesting that car has a 3-speed auto (A670). I am kinda surprised that an IROC car came with that transmission. I thought that it being a higher line optioned car it would have had the 4-speed (A604/41TE). At least the transmission you have is fairly easy to upgrade and work on, and less prone to screw up.

[Vigo]

Looks like a 604 to me.. Remember 670s didnt get actual dipstick tubes back then, and you can also just see the edge of the solenoid pack connector there too.

[lsm71]

Well she's back together and running with no leaks. I bought all new coolant tubes and the Gates water pump / timing belt kit but decided to replace the rear tube and see if that took care of the problem which it did. Thanks for the assistance, made my life easier for sure. Now I have a new fuel leak to fix under the car by the back passenger wheel and then maybe it'll be ready for a trip around the block...

This thing smokes pretty bad any suggestions besides a tear-down? Marvels Mystery Oil maybe??

[Force Fed Mopar]

Probably valve seals, they are notorious for leaking. They can be fixed in the car but I'd recommend a professional doing it.

[lsm71]

BTW it is a 4-speed Auto

[Ondonti]

If money is a concern you can do the valve stem seals by yourself in car, its just very annoying. My wife's 3.0 was abused by its previous owners and burns oil and lets out a puff of smoke after sitting for awhile. I ignore it but I know the piston rings are all gummed up from someone not changing the oil much. Less worried about the valve stem seals on that motor, the burning oil bothers me but not enough to tear apart the motor in a car I try to keep stock. Transmission is very abused as well. Just waiting for it to fail.

[Reaper1]

Looks like a 604 to me.. Remember 670s didnt get actual dipstick tubes back then, and you can also just see the edge of the solenoid pack connector there too.

Yup...you are absolutely right. I just didn't see it before. I focused on the tranny cooler line and was looking for the wires and such there. Man...I've been having a bad run of identifying things recently... :(

[Vigo]

Leak near the rear passenger tire is probably lines to the fuel filter.

[lsm71]

Fuel leak is fixed... the fuel filter was loose as mentioned above. Any suggestions as to where to start with a non functional water temp gauge? I purchased a service manual about two weeks ago but it still has been delivered....

Thanks!!

[Force Fed Mopar]

Coolant temp sending unit.

[lsm71]

Swapped out the sensor but no luck... the cooling fan doesn't come on either. Luckily the service manual I bought came today cause I obviously need it. Ugh

[c2xejk]

Fuel leak is fixed... the fuel filter was loose as mentioned above. Any suggestions as to where to start with a non functional water temp gauge? I purchased a service manual about two weeks ago but it still has been delivered....

Thanks!!


Swapped out the sensor but no luck... the cooling fan doesn't come on either. Luckily the service manual I bought came today cause I obviously need it. Ugh

Did you change the sensor (2-wire) or the sender (1-wire)? The sensor is for the ecu. The sender is for the gauge cluster. If you disconnect the sensor with the engine running, the fan should come on.

Ed Kelly - KMPerformance.com

[cordes]

If you ground the actual temp gauge wire it should peg the gauge. If not yo have a problem between the gauge and the sender potentially including the gauge itself. If that checks out then just replace the sender.

If the fan won't come on the jump the fan relay and see if it works. You can also run direct power and ground to the fan to test the actual fan.

[lsm71]

Ok that's fixed along with a few other things now on to the next challenge.

[lsm71]

Still working on the car... most of the little things are fixed, now its time to tackle the bis stuff: engine smoke and rocker panels. I've read a lot about the valve seals failing but it was supposedly fixed on 91+ model engines. Is it still likely to be the valve seals or could it be another more serious problem? As for the rockers I've read bad reviews on the aftermarket versions so I'm looking for a set of used ones if anyone knows of any. Thanks again

[Vigo]

Yes, it's still likely to be the valve seals. Regardless of whether chrysler fixed the valve guides dropping out of the head, there's no valve guide that's immune to just wearing out and letting the valve stem move too much inside the seal.

There are a couple guiding rules to go by when diagnosing engine smoke:
Does the engine smoke immediately upon startup? If so, the oil is being burned in the combustion chamber. Rings or intake valve seals.
Does the engine take a few minutes to really start smoking? If so, the oil is being burned after the chamber. Exhaust valve seals (or turbo on a turbo car).
Does the engine smoke worse under deceleration than under hard acceleration? Intake valve seals (because high manifold vacuum in the intake port makes them leak faster and low vacuum under load makes them leak slower).


Typically, it's intake valve seals (exhaust dont tend to cause as much smoking problems even if they are bad). Usually after the car has been sitting a while it will blow a good cloud of smoke upon startup and then slow down and puff a little smoke steadily. If you rev it up from idle it will shoot a big cloud but when you're driving and under load you'll notice the big initial puff will clear up and it wont smoke much as long as you stay in the throttle. Once you let off and let the engine decelerate (which is when it develops the strongest vacuum) it will trail smoke again.

[blk86trbo]

Excellent explanation Vigo

[RoadWarrior222]

However, the engine seems to have other quirks that makes valve seal smoking worse. In my experience it seems to get slight positive pressure under the front valve cover, this can be the result of two things.... one is the PCV passages in the front valve cover getting sludged up. The other is the top PCV hose that goes over the engine sucking flat, may look fine when cold, but the damn things can go soft when warm, particularly in city driving, and suck flat, then you're blowing huge clouds of blue... then you get home or wherever, probably have something to do, pop the hood 15 minutes later and it's returned to shape....

Anyway, preventative for the valve cover sludging and top end sludging in general, NEVER EVER EVER run oil thickeners, bardahls stuff, lucas stuff, whatever thick gloopy stuff no matter if it costs $100 a dose, DO NOT put it in there.

For remedial action, to clean valve cover PCV ports, at oil change time only, first, give it a blast of WD-40 into there, if a lot foams out, leave it sit for half hour, try again, then leave it soak 15, otherwise just leave it soak 15, then give it a quick blast of brake cleaner also. Shine flashlight through filler, see if you can get rid of any real black gooky bits with quick bursts. Drain oil, and while draining, drop a pint of kerosene in through the filler to help rinse the crap down.

Replace top PCV hose connection with high quality thick thick wall fuel hose, not the basic 10 psi carb fuel hose, the thick/rigid injection hose.

How to stop it getting so nasty, and clean it up while you drive, reduce smoking, make valve seals last a lonnnng time..... use 10W30 "High Mileage" oil in it... Pennzoil and Castrol are the good ones, the Mobil one is horrendous, avoid like plague... Anyway, either of those, it will start cleaning up, after a week or two it will stop burning and using oil, consumption will reduce A LOT. Change it out on schedule for the same stuff, it will keep everything sealed, but this H-M stuff, it goes "bad" quick after a change is due, so don't push your change intervals. It might seem expensive, but you are seriously going to use half to a third the oil you would otherwise be using in these motors. Also due to being semi-synth, you get the lubricity boost that synth gives you and slight mileage and power improvement.

Anyway, check/do that stuff and you might not need to replace valve seals yet...... and when you do, still do it, and you won't have to again.

[c2xejk]

As for the rockers I've read bad reviews on the aftermarket versions so I'm looking for a set of used ones if anyone knows of any. Thanks again

Why do you need rockers?
I should have some used ones. PM me.

Ed Kelly - KMPerformance.com

[lsm71]

Yes, it's still likely to be the valve seals. Regardless of whether chrysler fixed the valve guides dropping out of the head, there's no valve guide that's immune to just wearing out and letting the valve stem move too much inside the seal.

There are a couple guiding rules to go by when diagnosing engine smoke:
Does the engine smoke immediately upon startup? If so, the oil is being burned in the combustion chamber. Rings or intake valve seals.
Does the engine take a few minutes to really start smoking? If so, the oil is being burned after the chamber. Exhaust valve seals (or turbo on a turbo car).
Does the engine smoke worse under deceleration than under hard acceleration? Intake valve seals (because high manifold vacuum in the intake port makes them leak faster and low vacuum under load makes them leak slower).


Typically, it's intake valve seals (exhaust dont tend to cause as much smoking problems even if they are bad). Usually after the car has been sitting a while it will blow a good cloud of smoke upon startup and then slow down and puff a little smoke steadily. If you rev it up from idle it will shoot a big cloud but when you're driving and under load you'll notice the big initial puff will clear up and it wont smoke much as long as you stay in the throttle. Once you let off and let the engine decelerate (which is when it develops the strongest vacuum) it will trail smoke again.

Wow thanks for this great post! Now I just need to decide between buying some rebuilt heads ($250ish online) or have the seals repaired in place. Thanks again!!

[EaZyE426]

Wow thanks for this great post! Now I just need to decide between buying some rebuilt heads ($250ish online) or have the seals repaired in place. Thanks again!!

It'll be cheaper to have the seals replaced than the heads by a mechanic. Not to mention, who knows the quality of parts/craftsmanship of rebuilt heads unless from a reputable source.

[RoadWarrior222]

Yah the trouble with the rebuild industry is that they're fighting for survival, when most engines have improved enough that by the time a rebuild is needed the car is worth $500 or less, not like back in the day when ppl ran them hard and needed a rebuild every 60-100k. So they are trying to keep costs wayyyyy down so you even consider a rebuilt head etc, and to do that they are using the cheapest parts they can get their hands on. Parts suppliers are complying by producing parts that are less than original spec, for example, plain cast rings, when the originals were moly coated. (Have been in 90% of motors since the late 80s). Anyway, upshot is, the good valve seals are viton, unless that is specified as used in the rebuild, they could have something made from recycled chewing gum or something.