What to do when the head is removed? (Long)

[spyderturbo007]

Hello everyone, I normally keep my butt in the Tuning section but I thought I would ask for some help with my pending problem. This will be a long post, as I am going to provide you with as much information surrounding my problem as possible.

Right before I put my car in storage for the winter, I noticed an antifreeze leak in the area where the water pump outlet meets the main coolant line (the big one that runs under the exhaust manifold and connects to the thermostat housing). Alldata shows a o-ring in there but I'm not convinced that's my problem. The truth is, neither myself or my friend can determine where the leak is coming from.

We had it up on his lift (he owns an automotive repair shop) and really can't see much. I am unsure if the coolant line can be unbolted from the thermostat housing and pulled out of the water pump housing easily or not? It could even be leaking from the water pump itself. We have no idea.

He suggested that we go ahead and do a timing belt job, with all associated parts, since it has been 4 years / 20k since it was last done. This would allow us much better access to the water pump and the coolant line. Don't worry, I get all my labor for free, so I'm not worried about that.

You may be thinking; where does the head come into play in this guys rant.....

I'm glad you asked.

I have been wanting to replace my HG and head studs since I installed the EVO III 16g as I am afraid I'm going to lift the head if I turn up the boost anymore. So we figured that while we are doing the timing belt job, I might as well have the head pulled and the gasket/head studs replaced.

Here is where the questions come in. I have no idea what I should replace while the head is off. I was going through 5 or 6 pages of old posts and there is conflicting information all over the place. Not wrong information, just different points of view. Some like 4 layer HG's, other cometic, some Titan ICS, etc. I am just looking for the right one for me.

I see that the cometic's and the copper gaskets are hard to seal unless the head and block are polished beyond most machine shops limitations, so I think I will stay away from them. What about the mitsu 4 layer head gasket? What would have to be sent to the machine shop in preparation for that gasket?

Is there anything else I should do while the head is out. I have read all about 3 and 5 angle valve jobs; although I have no clue what that means, SS valves, titanium retainers, dual springs, etc, etc. All of that is way over my head.

I am looking into a set of FP cams to be installed when the head is out and was going to purchase the ones that are "compatible with stock springs". Should I just have the head decked and reinstalled or are there some cheap things that can be done to "beef up" the head while it is removed.

In conclusion (holy crap this has been a long post), I am also thinking about trying to fix the coolant leak by replacing the gasket and then attempting to install the ARP's with the head intact. Because truthfully there is nothing wrong with my head/HG, etc. Can the factory gasket handle 25 - 30 psi when used with ARP's?

What do you guys/gals think?

Thanks for reading my extremely long post.

 

[1fast97gsx]

I would compression test the motor to see if there is an obvious headgasket leak. If you aren't pusing coolant and oil and coolant aren't mixing I would leave the headgasket alone personally. There is an Oring that connects the larger water pipe with the water pump that could be leaking. I would do a timing belt job AND reaplce the water pump as well. When the pump is off just replace the Oring with the pipe still in place and install the new pump and gasket. If you have low compression readings ( primarily on cylinders 1 or 2 and oil and coolant are mixing then the headgasket is the problem most likely but I usually like to avoid pulling the head off. You can still do the headstuds with the head on the block if you do them 1 by 1. Since you will have the valve cover and the timing belt off this would be a good time to get a set of cams.

 

[bullettdsm]

I would compression test the motor to see if there is an obvious headgasket leak. If you aren't pusing coolant and oil and coolant aren't mixing I would leave the headgasket alone personally. There is an Oring that connects the larger water pipe with the water pump that could be leaking. I would do a timing belt job AND reaplce the water pump as well. When the pump is off just replace the Oring with the pipe still in place and install the new pump and gasket. If you have low compression readings ( primarily on cylinders 1 or 2 and oil and coolant are mixing then the headgasket is the problem most likely but I usually like to avoid pulling the head off. You can still do the headstuds with the head on the block if you do them 1 by 1. Since you will have the valve cover and the timing belt off this would be a good time to get a set of cams.

Repeated for emphasis. I also would not pull the head unless you get low compression numbers. Water pump and cams dovetail nicely with what you are doing. Don't worry abou the springs. Your stockers will do fine with the fp 2's. That is the set-up I am running right now. Though I am only pushin' to 20.
MB

 

[spyderturbo007]

Thanks for your replies.

I guess I should do a compression test when I get the car out of storage first and verify that it's not the HG leaking. Then I guess the next logical step would be to try and see if it's the O ring that went bad and try to avoid doing anything with the timing belt at all.

I know the belt is in great shape because we inspect it from time to time.

So if I get good compression numbers and can fix the leak, you both recommend that I keep the factory HG and just replace the head studs using the quick method of leaving the head on??

Will the stock HG take the pressures I am looking to run. Hoping to finish around 38lbs/min airflow, which by my estimation will happen right around 25 or 26psi.

Thanks for the heads up about the cams!

 

[bullettdsm]

Maybe you misunderstood me a little. I WOULD do the timing belt regardless. You have had coolant leaking on it for a while. This weakens the belt. These belts don't generally stretch but they will strip (http://www.dsmtuners.com/forums/showthread.php?t=204667 as seen by recent post on site). I would let a little oil on the belt go by, but any coolant leaks I replace belt (generally coolant leaks on the belt are waterpump sourced anyway). Now if you do the timing belt, then the water pump/cams do dovetail nicely with what you have already taken apart.

When you do the arps, do them one at a time but not to full torque. Arp's numbers are somewhere around 75 (I don't remember the exact number but I just did them and it is around that). Generally, everyone goes much higher than that. I torqued mine to a final 93. I have seen numbers on this site of up to 115 (I believe that was a wiseman so he should have some experience) and I personally know of a DSMer mechanic who goes to 110. Torque your studs to 70 as you replace them and THEN final torque them to a number of your choice (of course remembering your pattern). Also, keep in mind that you may have a head stud pull and then you will have to pull the head .

As for the head gasket; there is so much information/misinformation on the headgasket I can only go off my personal experience (which is limited with these headgaskets) and the experience of the guys that I personally know (who's experience with the DSMs is extensive). The stock head gaskets are pretty strong. That coupled with the ARP head studs should do you just fine. I have only spiked up to 25 on my car so I really have no first hand knowledge of the numbers except to say that mine does 20 no problem and I used mitsu on my rebuild.

I'm sure that others would chime in but if you searched (as you did) then you will find that to be a VERY grey area. I would personally be confident in using the mitsu.

MB

 

[droptopgst]

Sounds like the problem that I had with mine. It ended up being the o-ring on that pipe. Put a new one on and no leak from it since, well until I put the 50 trim on and turned the boost to 23-25psi. Now I am pushing coolant.

I would leave everything alone until you replaced that o-ring. With only 20k on the t-belt, it would be over kill to change it. I have 80k on mine now, will be changing it soon (next week) but would be a waste to change yours unless there is oil/coolant on it.

I ran up to 24psi (daily) on my 18g with the stock h/g and h/bolts with no problem. close to 300hp/tq. I would not waste your $$ on things that dont NEED to be replaced yet.

Now if you are in fact pushing coolant, are close to the 70k mark on the t-belt then go ahead and do it all. If not then just hold off until it needs to be replaced (if its not broke dont fix it) type thing.

Tune good and keep up on the maint. of your ride, you should be problem free!

 

[spyderturbo007]

It ended up being the o-ring on that pipe. Put a new one on and no leak from it since,

Ah, beautiful.....I was hoping someone else would have this problem. Can you tell me how you went about replacing the O-ring?

Was it as simple as unbolting it from the thermostat housing and pushing the pipe towards the passinger side of the engine bay? Can you reach the O-ring that way?

If it's that easy, I think I'll just replace the O-ring and leave the timing belt alone.

Thanks for the heads up about the timing belt bullettdsm, but my mechanic and I thoroughly inspected the belt and found no coolant, oil or anything else on the belt or near any of the covers. So I think I'm ok there.

I think this will be my game plan:

1. Compression test to verify that the HG isn't leaking.

2. Replacement of the water pump O-ring.

3. Replacement of stock head studs with ARP head studs

I think I'll try raising the boost on the stock HG. If I blow the HG, It's not really a big deal, as all my labor is free.

Does that sound like the correct plan of action to you guys?

Any other suggestions would be appreciated.

Now it's time to hand out some rep points. Thanks to everyone who replied.

 

[wolf20043]

It would be easier to change the o-ring with the water pump off. It sounds easy to slide the water pipe to the passenger side, But the bend in the pipe gets in the way of the turbo and other water lines and makes it a PITA.
Mike

 

[bullettdsm]

I think this will be my game plan:

1. Compression test to verify that the HG isn't leaking.

2. Replacement of the water pump O-ring.

3. Replacement of stock head studs with ARP head studs

Sounds like a plan. I have only done that O-ring switch with the water pump off (lot's O' practice with timing belts so no trepidation). I had to change a hose off that water pipe one time and it was a PITA to get to (as wolf20043 had said) with all that "stuff" in the way. But good luck to ya.
MB

 

[droptopgst]

any update?