F14CRAZY

Supercharging (this time, it's real)

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Padgett,

The S/C runs two belts so the L-67 Harmonic Balancer is a necessity with the Blower. I'm wondering if there's some misalignment issue between the Crank Sensor mounting from the 3.8L to the Series I. Off-timing fits with the performance issues Philip had.

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Hmmm...we have established that the harmonic balancers are the same at least as far as the relation of the "rings" to the keyway.

I can take a look on my L67 block to see if the position of the CPS itself is different when I get back. Not sure if I saved the CPS that came with the L67 cuz it was cracked, but I think I have it.

I'm going to review the pix in my server and see if I got the comparison pic

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Blast. Pix are at home. I'll re-post it when I get back.

I don't think I examined them as closely as I should have when I installed the CPS but I didn't notice any significant difference

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Went to the local dealer (Crippen) and bought a gasket. Took it home and it's just the same as the ones from Advance...not quite right. I returned it (eventhough it was open, they didn't give me any trouble). Called my dad, and he suggested to pickup a roll of gasket material and make my own...

I've got it cut and am going to go back outside and assemble. Should be able to start it up this evening

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I need some help guys...

Ok, got my custom gasket all cut out and reassembled everything all back together...

Still not running. Same as before...can get it running for a few seconds if lucky, but that's it. Also, I'm still getting a lot of white smoke. Could it be leaking yet again?

The gasket I got from the GM dealer was a different brand from the one at Advance, but was pretty much the same exact design as I've shown in the photos. It just isn't quite right. I thought Advance was giving me the wrong one, but the GM dealer gave me the same thing. I asked the counterperson and he said that the same gasket is prescribed for the L67 from '91 to '95. I asked him about it because the earlier ones had a little less HP and I thought might have been of a different design, and that maybe the engine I got was changed, but no.

I tried for maybe 10 minutes to get it started, with starter-rests and fuel pine checks in between crankings. As I said, I'm still getting a lot of white smoke. I probably should have removed the plugs and turned the engine over to blow out any remaining coolant, but I did a pretty good job from the top, and its been sitting for about a week now anyway. Would there still be remaining coolant, or is the leak back? I made note of the level of the coolant in the radiator tonight and will check tomorrow if it went down.

What do you guys suppose is wrong? Is my intake manifold and supercharger not compatible? Doubtfully, since it came from the same, running engine. With this coolant leak, would it still run? Do I have a more serious problem like holes in the pistons?

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I've had the Blower on and off twice on mine and don't recall the gasket not fitting?

What's been changed? You've installed the S/C intake on your 3.8L engine, there's a possibility of one of those intake gaskets going south. I'd suggested over the past year any time this was discussed that gaskets from the two generations be compared? Blown Head gasket is the other source of coolant?

From your attempts weeks ago, it's very likely there's still coolant in the cylinders, it won't evaporate so has to be blown out or burned out.

I think I remember you mentioning in a Post there could be a posssibility the key fell out when you were installing the Harmonic Balancer. If you've got fuel and ignition it will run unless the timing is off.

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I can go after the plastic/rubber intake manifold gaskets again. Possible they went bad. Note though that they were new and I torqued them to spec (8 pound/ft). In my earlier comparison of the LN3 and L67 intake gaskets, they only difference that could be found was that extra round hole. General design, thickness, etc were the same.

Wouldn't my 10 minutes of cranking have blown or burned out any coolant left?

If it's still not running after I figure out this leak, I'll check into the balancer. I suppose the key could have come out and causing timing to be off.

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Went out with my dad to see it again. Coolant is leaking out of the engine, again between the S/C and the manifold. I have a life and need to do other things, so I at least pulled the lower hose to drain the system so it won't flood the engine with coolant.

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Need a position check here. What was going on got a bit blurred around 2/24 on page 2. You had a complete L-67 but then were talking about putting the S/C on the original LN-3 which was why I thought you removed the intake and didn't just bolt the whole thing in.

Which did you wind up doing ? Replaced the whole LN-3 with the L-67 or put the S/C, accessories, and manifold on the LN-3 ? Somewhere I got the idea it was the latter which might be a clue to the leaks.

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I posted my leak problem on the Bonnevil... yellow O rings

Padgett: I did the route where I bolted on the L67 parts to my LN3. A complicated mess, yes, but that wouldn't explain why the S/C and intake manifold gasket is leaking...both of those units came from the same engine. Unless work has been done before, they came from the factory bolted together. Shouldn't matter what it's bolted to, as long as the S/C and manifold are matching (which they are).

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Am thinking it would not take much of a warp when bolting down the assembly on the heads to cause a leak. Something is niggling my brane about deck height and manifold mismatches with milled heads but might be series I/series II.

Really old time fix is to double gasket it but am not sure what that would do to the O-ring seals.

Did find this at a web page

"Special notes considering the differences between the Series 1 L & C 3800 engines: The vin L 3800's cylinder heads were the first to feature an integral PCV ventilation system that was found in all subsequent 3800 and 3800 Series II engines. This means that the earlier vin C 3800 heads will not work on a vin L 3800 engine. "

But dunno about an L intake on C heads. Am just throwing out thoughts since there is obviously an issue.

And just for a ringer, when we took my son's Quad Four appart to cure an oil leak, we found so much sealer in the bolt holes that there was no way to torque it properly. Had to clean all of them out first When you remove the manifold the next time you might check all the manifold bolt holes to verify that no bolt is bottoming and torqueing without compressing the gasket. And along that line, any chance the LN-3 manifold bolts are longer than the L-67 or verse da vise ? Might be designed for more threads in case of a blower explosion.

Something is mismatching and we need to find out what no matter how unlikely. Isn't there a way you can use plastigauge under a manifold to verify a fit ?

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Well now you are going to have to fess up to the Bonne Boys and tell them that you are trying to mate a Pontiac and a Buick. It may help them understand a little better what you are up against. They sound knowlegable.

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I'm using the L67 bolts...the LN3 has a one piece intake manifold, so I didn't have any bolts to use from it.

The built in PCV may be the reason for that extra port I found earlier in my quest, like when I compared the L67 and LN3 intake-to-head gaskets. It just sits there. Don't see why it wouldn't work

sc19.jpg

The Bonneville guys (dude with like 29k posts) said I could drill, tap, and plug those coolant holes. They're not needed. Only to keep the throttle body butterfly from sticking, which he said isn't an issue.

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Don't have to say anything about Buicks, just admit you want to put an L-67 blower on a "C" long block and see what happens.

What happened to the rest of the L-67 engine ?

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I'll do that.

I've still got the L67 block and parts in storage. Might come in handy someday, or if I ever give up on this and decide to put the whole thing in my car

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If there aren't any visible cracks, and the o-rings haven't cured the problem leak, I agree you should tap the holes and plug them. I know mine is a summer only car but I do drive it into late fall before the snows, where temperatures can get down well below freezing. I plugged the throttle body heater ports years ago. I have never found a driveabilty problem without them. On a VIN C it makes removing the throttle body a snap without the pesky tubes.

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Lets take a step back here. I think there is a possibility you might have popped a head gasket and the pressure from the cylinders is getting into the cooling system and blowing out your little o-ring seals under the SC.

The best way to check for a blown head gasket is to do a cylinder leakdown, or put compressed air into the cylinder. (auto parts and tool stores sell a hose that screws into the spark plug hole and allows you to hook up your air compressor hose to it). You will need to turn the engine over so each cylinder you test is a Bottom Dead Center after the power stroke.

A blown head gasket may also show up on a compression test as well. You might also want to check your oil and make sure the level has not increased and it hasn't turned into chocolate milk.

I would perform this check before worrying about your SC gasket sealing issues.

-ryan

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My analysis before I read Ryan's post...

I removed the S/C again today. Both the gasket and O rings seemed to be dry. Lots of coolant down in the intake manifold. Hmmmm...

The Bonneville club board suggested today that my throttle body to S/C gasket was leaking, for this is where the throttle body gets its coolant to be heated (you know, people spend hundreds of dollars on cold air intake kits...). So, I removed the throttle body. Can't tell by the gasket if its leaked here, but I was missing one out of three bolts (yes, my fault, not good) and there was coolant in the throttle body and even in the air filter.

The important part: when I first got this stuff together and started up, there didn't seem to be a coolant issue. Recall that my leak problem began when I was waiting for Ryan's 2nd and 3rd ECM programs. And recall my WOT tests...the throttle body gasket was sealing fine, but due to the missing bolt and my lack of measuring the torque on the bolts (I never knew there was coolant running through it) it eventually broke loose. At around the same time, more or less, the head gasket went bad. The throttle body got worse, letting more coolant into the intake. Boost from the S/C got it to leak from the area under the throttle body, I'm assuming because this is the path of least resistance for it to leak out of. Coolant doesn't belong there at any rate.

I checked the oil today and found it to be watery and maybe half a quart high. Dumped it and the filter and found quite a bit of water. All I can say is that it's good that I haven't actually been running/driving it.

Adventures in Reattas. Enough coolant where it shouldn't be to make a grown man cry.

What's next? Should I do a compression test? Would have to either borrow a gauge (or the air compressor tool) or buy one. Should I go ahead and order and replace the head gasket? I obviously need the missing bolt and a new gasket for the throttle body. Since I'm going to have the heads off, should I look into using an L67 head gasket? Should I use the L67 heads?

What a mess! Thank you

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i think you should try the compression test before any thing. and honestly i wanted to see if this whole scheme worked before attempting it. (well i'd have someone else take care of the wrenching.)

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I defer to a suggestion made probably months ago to not put an S/C on a tired 3.8L

A set of head gaskets will run you some dollars, if you're pulling heads logic tells me you do valve seals maybe some porting/ clean-up while you've got the top end dismantled, otherwise;

I'd strongly suggest you cut your losses, pull the 3.8L and drop the Series I engine in there. You apprear to be trying to re-invent a wheel nobody would be particularly interested in. Sorry Philip, I have really not seen any potential in what you've been attempting. There's an abundance of 3800s' out there 7 or 8 years newer then the average Reatta motor. Horse Power is only fun if it's also at least somewhat reliable.

My .02 cents worth.

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I'm thinking about the same thing right now, Greg. My route looked good in my head but it's quickly becoming an expensive and complicated mess. With as much effort and money as I have into it, I could have very well used the L67 I bought instead of this conversion.

It does make more sense to put in the L67, though preferably without any disassembly, but if things don't get better really quick, I'm going to abort the conversion and swap in the rest of the L67 I have.

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from Willwren, Bonneville Club admin...

<span style="font-weight: bold">Sounds like we got 'er licked though. Use L67 gaskets if you use LN3 or L67 heads (assuming they mate correctly) as the L67 gaskets are designed to handle the increased effective compression. Do not re-use old bolts. The head bolts are torque-to-yield, and stretch when torqued. One time use only.</span>

I copied my post from earlier and posted there, and that's what he said. My project is at an all-time low right now, yes. But, it's a project. A challenge. If I could start at the beginning again I would have swapped out the LN3. It's much better.

My dad, with 33 years in plumbing, said he's never let a job whip him. This car won't whip me.

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Version 2 of software is always the hardest. You keep patching version 1 past all sanity before it sinks in that you are really better off with a complete rewrite.

I really think you would be better of building a complete L-67 with no concerns about tapered vs slip balancers, mismatched deck height, or anything else.

A major tune up while out would be in order (new freeze plugs, timing chain, plastigauge the mains - all easy when on a stand and a real bother in a car.

Just keep in mind that while "try, try again" is a good rule, trying the same thing over and over and hoping for a different result isn't.

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