Blew up top end I think (1987 GN)

[bmackinnon]

Before I start tearing this thing apart, are there any gotcha's I should know about during disassembly? I want to unbolt the least amount of stuff as possible. Can I pull the head without >removing< the exhaust header? I know I have to unbolt the header, but does it have to be physically removed in order to get the head on/off?

Make sure you take careful note of where all the exhaust manifold studs/bolts go, so they can find their way back to the proper homes. Maybe even take a couple pictures. Check your headers VERY CLOSELY for cracks while your at it. They ALL crack, and now would be an ideal time to take care of that. GNTTYPE.org has pictures of where the cracks usually reside. 6-banger above is oh-so correct. Check your PM... :smile:

 

[GSTOY]

See my earlier post. I guatentee it can happen, I'm living proof.

http://www.turbobuick.com/forums/engine-tech/252588-ahh-head-gaskets-oil-bath.html

It's the head Gaskets...trust me ") If you go with the 9441 felpro's spray some copper coat on the gaskets before installing them

Steve

 

[ericmccann]

One other thing I just thought of is I have no idea what chip is in the ECU. What would the stock ones look like/what should I look for. The PO had a lot of gauges in the car - all removed. I'm suspecting that there may be a custom chip in it too. I need to check - rapidly.

Thanks everyone!

Eric

 

[ericmccann]

Again, I'm having a noobie moment. What is this copper-coat you speak of. I'll definitely get it if you guys recommend it and if I know exactly what it is and where to get it.

Thanks!

Eric

 

[GSTOY]

Its made by permatex, it's called copper spray a gasket. Make sure you get some gloves, this stuff is messy to spray on, but it's good for HG's. Also spray on both sides of the HG.

Also, if you blew the HG's really hard into the valley pan, it might be good insurance to pull the oil pan. Mine was coated in blown HG material on the oil pickup screen and all sorts of trash in the bottom of the pan.

+1 or whatever were up to on the recommendation to get the ARP bolts. I went back in with studs, they spread the load better, but either way, bolts or studs, you won't have to buy anymore headbolts. On the Torque to Yield bolts from the factory, once you pull them out, they are useless since they have stretched.

Another note on the bolts. The 4 upper bolts closest to the intake, are longer than the 4 on the bottom row. Of the 4 upper bolts, the 2 middle bolts are the longest ones.

Steve

 

["Turbo-T"]

One other thing I just thought of is I have no idea what chip is in the ECU. What would the stock ones look like/what should I look for. The PO had a lot of gauges in the car - all removed. I'm suspecting that there may be a custom chip in it too. I need to check - rapidly.

Thanks everyone!

Eric

Sounds like a good excuse to spend an extra $80 for a Turbo Tweak chip. Good chips, they allow you to adjust your fuel and timing curves plus they're good for todays fuel. If you don't have one I'd add one to the list.

 

[ericmccann]

I think I might know what happened to cause this.

I think I know what happened to cause this. Looking really close at the motor (pre-dismantle), I noticed a vacuum line was disconnected from the EGR VAC Regulator. It was close enough to the actual vac line connector to make me believe that it had been connected prior to this event. What I'm suspecting is that during boost, I was only seeing 10#'s of boost because I was losing a lot of extra pressurized air in the VAC lines. This, in my best guestimation, caused the wastegate solenoid, the wastegate itself, and the fuel pressure regulator, the EGR VAC regulator, etc. (well, everything off the VAC block) to not read accurately. I suspect that I was creating far more boost than what the guages showed, and the fuel pressure regulator never provided more fuel as necessary and the wastegate never opening up, thus causing a lean condition and me blowing up the head gaskets.

Does this sound at all plausible?

Thanks everyone! I'm trying to go through this in the most methodical manner I can.

Please let me know your thoughts on this little theory of mine.

Best,

Eric McCann
Germantown, WI

 

[ericmccann]

UPDATE: More disturbing findings... (I'm in tear-down mode right now)

Just wanted to post an update as to my findings thus far. I noticed a large (at least 1/2 I.D." port) port on the intake side of the turbo (facing toward the rear of the car) which was connected to nothing, thus sucking in non-metered air whether under boost or not. I suspect that this port should have been either capped off with a rubber cap or connected to something else unknown. This is such an obvious oversight by a previous owner. I'll blame myself too though since I jumped into this GN thing with both feet.

Any thoughts, folks?

You will all learn that I'm a 'root-cause' sort of guy. I can accept things happening just fine, but I also what to know why they are happening.

I still love this car and I feel VERY fortunate to own one.

Cars owned by my GN: 1970 Chevelle 396 SS (not even a contest)

Best,

Eric McCann
Germantown, WI

 

[79TurboCutlass]

This port you speak of sounds like the port the right side breather was connected to. It should have a rubber plug on it to block it off.

 

[ericmccann]

That's EXACTLY what I thought, considering it's location. I had the SAME EXACT issue with my 1981 Fiat Spider 2000 - with a Garrett T3 turbo - in that where do I vent this thing? I've learned a lot about boosting from that little Fiat motor.

I saw that port on the turbo on the GN and thought to myself - 'that thing needs to be connected to a vacuum hose somewhere.'

Do you have any idea where I can find an original breather hose from the turbo to the passenger side valve cover?

Thanks so much for replying and reading through this thread.

Best,

Eric McCann
Germantown, WI

 

[79TurboCutlass]

I may have one around. I can look. You could also put a little breather in the valve cover and block off the port in the intake tube. Full Throttle has a kit with breathers for both vavle covers.

 

[ericmccann]

Oh, I'm so right there with you, 79. I even already had a rubber port cap for that opening off the turbo. If only I had known it was there. Alldata sucks for vac diagrams on these motors - as well as the electrical.

Here are some pictures I took tonight.

1987 GN motor - initial findings upon teardown - a set on Flickr

Again, I'm being VERY methodical in my approach so please don't yell at me for not showing head gasket failures yet. Those pictures will come...

Best,

Eric McCann
Germantown, WI

 

[JSTTA]

Consider head gaskets as fuses, the person who sold me my TTA gave me that analogy. Better the fuse blowing then the bottom end.

 

[jhanson1750]

Just so you know. If you blow off a vac line on the motor the waste gate SHOULD still function correctly. The vac line for the WG is routed from the refrence port on the scroll cover to the WG actuator and to the WG silinoid (sp?). But with the combination of un-metered air and loss of fuel pressure the HG don't stand a chance. Good call on the ARP's and stock type HG. When you get her back together do yourself a bid favor and replace ALL the vac lines on the engine and put a tie-wrap (zip tie) on both ends to keep the lines from blowing apart under boost. A little thing that saved me was there are a couple of lines that you just cannot get a zip tie on, unplug it and put a drop of super glut on it and put it back together. If you ever have to remove them you can use a razor blade and cut the vac line off of whatever nipple it's on. Jon Hanson

 

[bmackinnon]

+1 on all accounts.... never heard of using super glue?? Don't see why it wouldn't work, though. Eric, you have PM... :smile:

 

[ericmccann]

Thank you so much for the feedback. I was hoping that someone would chime in. As soon as I saw the things I saw, I understood why what happened, happened. Now, looking forward, with the help of all of you here, I know what to watch out for, what to get, and how to prevent this from happening again.

I talked with my wife about this tonight and she was really cool about it. She basically doesn't care how I get it fixed, but just so long as I get it fixed because she really likes the T-tops and my young kids love the car too. Again, I didn't intend for this to be a race car at all and it will not be. It should be streetable though and enough so that I don't have to worry about popping gaskets every time I get on it. Now that I know what caused it, I know what to watch out for.

Certainly, the Scanmaster is a must!

Thank you to all for your kind and well-thought advice. I'll continue to post Flickr albums of my prgress and post those links for your reference. Pictures are a good thing! Here are some of the kids in the GN: My kids like the 1987 Grand National too - a set on Flickr

Best,

Eric McCann
Germantown, WI

 

[JST A 6]

Eric,

I noticed in an earlier post way up the list you said it looked like the car had been running lean previously when you took out your old plugs. Besides getting a Turbo Tweak chip and Scanmaster, I'd also replace the stock fuel pump with a Walbro 340 or Quad Air XP pump, and get a hotwire kit on it too to make sure the pump is getting plenty of power. The stock fuel system on these cars is barely adequate even for a stock motor. Also, an adjustable fuel pressure regulator wouldn't be a bad idea, or a "237" regulator if you want to keep it stock appearing but gain an extra few pounds of fuel pressure. I have a "237" I could sell you if you want to go that route. Other than the above, change your fuel filter and your fuel system should be in good shape. Just a little extra insurance against running it lean again.

Only other thing I can think of at the moment is maybe an RJC powerplate. On these cars the #5 & 6 cylinders tend to get more air rammed into them than the other four so they tend to run a lot leaner than the others. The powerplate is designed to even out the distribution of air to all the cylinders, and it's barely detectable once installed on the car.

I agree with those who suggested going with the Felpro head gaskets--it could be that they blew for a good reason on your '79. In case you're not already aware, running the highest octane fuel you can is a must with any engine under boost to avoid detonation. My neighbor across the street bought an '86 T Type and he runs 87 octane in it all the time, even when he took it to the track once! He got the car just because he knew what it is--he doesn't know anything else about it, is not really "into" these cars, and is very thick-headed about listening to those that do know what they're talking about so I'm waiting for him to blow a head gasket or worse. I run nothing less than Sunoco 94 octane in mine and I run the boost at a very safe level, about 16 psi. I never see much more than 2 degrees of knock retard on the Scanmaster and even that's somewhat of a rarity. Hope something I said helps...Oh yeah, change out your thermostat to a 160 degree one and block off the small coolant lines going to your throttle body--running cooler engine & intake air temps is also important to avoid detonation.

 

[turbofabricator]

Eric,
Here is a MUST DO list when R&R cylinder head gaskets:

1) Fel-Pro 9441pt head gaskets, or OEM gaskets (virtually the same thing)

2) ARP head bolts, use teflon thread sealant on the threads, and ARP lube on BOTH sides of the included washers. (20w50 racing oil will work, too)

3) Walbro 340 in tank fuel pump

4) Fuel pump hot wire kit (from any of the vendors on this site, or make your own)

5) Adjustable fuel presure regulator (again, any vendor on this site)

6) New valve springs, valve grind, seals. (do NOT have the machinst touch the valve guides UNLESS they are bad. I have seen way too many machinsts SCREW-UP valve guides. Do NOT install valve seals on the exhaust guides unless you step up to aftermarket stainless valves. A good three angle valve job is a good step, pocket porting the heads will net you 25-30 hp., for just a few bucks. Verify the head surface and mill IF it is more than .002" out, if it is not out, LEAVE THE DECK OF THE HEADS ALONE!!! Have the rocker pedistals ground down to clear roller rockers in case you decide to go that route in the future. It only takes a few minutes to do now with the heads off. Have the machinist set the spring seat pressure to about 90 lbs. closed with new springs and a stock cam.

7) Install all of the electrical grounds on the boss of the intake manifold under the coil pack. It is the boss that the factory wire loom bolts to. Leave the loom un bolted, as it makes it easier to R&R valve cover gaskets in the future. Be SURE to file the top of the boss down a little to remove all the factory epoxy paint. I also add a short ground wire from this boss to the fire wall. Grounds are REAL important on these cars. You will have to cut some of the electrical tape off of the wiring harness to get enough length to reach under the coil pack, but there IS plenty of slack in there to reach. (OR, you can buy a ground kit from Caspers, and it will do the same thing)

8) Replace the vacuum hoses to the wastegate solonoid and actuator with fuel line, NOT vacuum line. Fuel line will hold up MUCH better over time. They DO make fuel line in 3/16, 1/4", ect. Go to NAPA and get it. I use fuel hose or push-lok hose for all boost control applications. You DON'T want these hoses to fail, or it WILL casue a repeat of what you are going through.

9) Get with someone local that has done LOTS of head gaskets/engine builds and ask them for pointers. You can also PM me and I can help walk you through it if you need help. Doing your own work is a GREAT idea.

10) Check the headers for cracks. They ALL crack. Just weld them up, and you will be fine.

11) After torquing the head bolts, wait 15 minutes and then, go back and individually loosen each bolt and then go to full torque again. It dosn't matter what pattern you do this final step in.

12) Use a light coat of Ultra-Black silicone on both sides of the intake gaskets around the water ports. Use non hardening Permatex aviation sealant around the ports, but use it sparingly.

13) Install the factory style head gaskets COMPLETELY dry. The gasket is a graphite compound and nothing will stick to it anyway. A wasted step to spray anything on them. They are engineered to be installed dry.

14) Have your injectors flow tested/cleaned, or step up to a set of MSD 50 lb. injectors or even the 60/65 lb. Motrons with a matching chip for what ever injectors you buy. I really hate to install stock injectors, even in a completely stock engine. Most guys want to keep adding power as time goes by, so why not use a good injector now. The MSD's will still give you good fuel economy.

Here is a list of things that woud be a good idea now that the heads are off:

1) Ported stock heads. The ONLY down side to ported iron heads is the cost.

2) Bigger turbo. TE-44, or similar, will net you about approx. 75 hp over stock and will still work good with a stock converter.

3) MAF translator and a 3.5" MAF. THe stock MAF's are no longer available and upgrading now is a good idea, though not required.

4) A 3" down pipe will net you approx. 25 hp over the stock kincked up 2.5" and cast elbow.

5) A test pipe and high flow exhaust Another 20-30 hp.

6) A stock location intercooler. Good to about 600 HP. Stay away from front mount intercoolers unless you get a killer deal on one. The stock location I/C from Precision is a real nice piece.

7) None of these mods will hurt driveabilty, except in the rain. :biggrin:

 

[ericmccann]

I'm not ignoring anyone here today, just working on yard projects. :-(

Anyway, turbofabricator, I understand and appreciate your advice with regard to my motor. I did find a few misc components in the trunk again today - a walpro in-tank fuel pump and something about a hotwire kit. So, it looks like I have that already - which is good.

My main concern is keeping costs down on this. I know that many of you are horsepower enthusiasts with these engines (and there's most certainly NOTHING wrong with that), but that's not where I'm coming from. I enjoy this vehicle for what it is and especially in as close to stock form as possible. In my case, I am so lucky to have found my 1987 GN and love owning it. Just so you understand where I'm coming from, I've spent years sinking money into Italian cars (and before that, my 1979 Turbo Regal - my first car ever) and I simply don't want to do that again. I did it with my '79 Turbo Regal - spending every penny I had to rebuild it. I did the same with my Italian cars. I understand the addiction of the turbos on these cars - I have since I was a kid (18 years old when I first had my '79 Turbo Regal). However, in your defense, the rush I got from that car, the feeling of pride by having one, etc. is a LARGE reason why I wanted, sought-out and purchased my 1987 GN.

My budget is not what it used to be. I cannot buy whatever I want just because I want it right now. This is mostly due to taking huge losses in my other cars. This car, the 1987 GN, gives me a slight chance to right all of the wrongs with my auto ventures. I'm a do-it-yourselfer; always have been, with the exception of machining work.

Please understand that I'm not impuning in any way, shape or form of your MUCH APPRECIATED advice, however, I just don't have the cash to do all of that right now - nor do I really want to - yet. Trust me, it's VERY difficult for me to say that.

I would love to get tons of HP out of the motor (which in stock trim is adequate for the wife and kids), but I'll be doubly honest in that after the events of the last week (blowing head gaskets), the absolute LAST thing I want to do is to take a chance and sink $$$$'s into this engine just to grenade it again. Other than owning the car, I have enjoyed driving it for about 5 minutes - literally. That was an EXPENSIVE 5 minutes which I don't care to repeat.

I truly admire your knowledge of these motors and I wish I could do all of the things you suggest, especially since you indicated that those changes would not affect drivability, but again I have to start in a place that I feel comfortable and which my wallet says yes to. In my case, it's getting the engine back to baseline and making changes one-by-one as cash flow and desire permits. Again, I want to bring this car as close to stock as possible.

After owning this car for less than 2 weeks, I already have at least $1500 into it in missing trim, emblems, radio, center colsole faceplate, sensors (oh my goodness, sensors), plugs, wires, lighting, etc. Now THIS!

The car already has a test pipe installed on it. No cat anywhere to be found. Straight pipes off the CAT flange back to a collector muffler tucked in front of the gas tank. I suspect this was the stock location for the muffler? This, I don't like at all. Even on my '79 Turbo Regal, I put dual pipes on off the CC flowing into dual mufflers underneath the car (true dual-exhaust design). I do want this for my GN. It may not be stock, but it certainly looks cool - and with the test pipe I already have, it should provide some HP.

Again, I appreciate your well-thought and well intended advice. I wish I had the budget and desire for it all, but I'm just simply not looking for a ton of HP right now. I just want a drivable car which I do not have to worry about breaking down with my wife and kids if I decide to push the throttle to the floor.

Best,

Eric McCann
Germantown, WI

 

[JST A 6]

Eric,

I kind of sensed what you were looking to do with your car before you wrote that last post just now, which is why I listed just a few simple things you can do to keep the car very much stock and make it a lot more reliable without spending a ton of money. The mods I listed won't do much if anything to improve performance but rather will help keep you from running it too lean therefore making it more reliable.

You mentioned that the previous owner had some gauges in it--did he also install an adjustable wastegate actuator? If so, you should get some sort of boost gauge and find out what boost level it's set at. 17 lbs. is about the max boost you can run on pump gas without asking for trouble, and even that can be a bit high depending on the individual car.

Other than that, put your fuel pump/hotwire kit in and maybe do some of the other stuff I mentioned earlier and you should be well on your way to getting what you want out of your car. The RJC plate I mentioned runs about $60 I believe, and adjustable fuel pressure regulators start out around $100-$120 but I've got the stock-appearing 237 regulator I would sell to you for much less than that. I've also got a great-working set of 36 lb. Bosch 868 injectors that I took off my car when I went to the 50 pounders so I would have a better match to the turbo the previous owner installed on my car. The 868s are a good replacement for the stock 28 pounders. You'd have to get a chip burned for them but you've already mentioned wanting to do that anyway. I've got a Caspers Ultrachip that's burned for them but IMO it's nowhere near as good as a Turbo Tweak chip. Good luck!