F*#$ing Headgasket!

[Tony D]

it was a case of the cigarette lighter was currently powering the laptop, which cut the LM1's powersource out.

 

Simple answer to that one, get a 2:1 splitter. I get them at truck stops, you can power as many as four low-draw items from one cigarette lighter.

 

I had splitters on splitters powering reading lights, fans, cel phone, gps, laptop, you name it, on my last cross-country with the Fairlady.

 

Get a splitter, and use that WBO2!

[TimZ]

Just for everyones clarification...

 

the car had the following before the fel-blow took dump...

 

MSnS with a proven tune (though it's up for debate on CR differences obviously)

 

Hopefully it's starting to sink in from several other posts' date=' but there is no such thing, unless it's been proven good on [b']your motor[/b]. This is especially true for speed-density systems, as is used on most aftermarket EFIs (including MSnS). Even if the CRs were the same, "pretty much the same" is nowhere near being good enough to just plug and play. There are so many subtleties that can have a significant effect on your AFR (the voltage issue you mentioned is just one of them) that you should only use someone else's tune to get your motor running and then tune it yourself from there. Sorry you had to learn this the hard way.

 

Also, checking timing with a timing light will only verify that the timing matches the timing marks on the crank pulley. It will not verify that the crank pulley is correct.

[Guest bastaad525]

Do you STILL feel that way??? HKS, then Nissan, then Stone, then about 20 more cheap *** Chinese headgaskets down the list... FelPro. IMHO...

 

 

agreed. while some have run felpro's with no problems, there are quite of few of us who've failed felpro headgaskets on L28ET's, myself included. Go with Nissan or HKS.

[TimZ]

agreed. while some have run felpro's with no problems, there are quite of few of us who've failed felpro headgaskets on L28ET's, myself included. Go with Nissan or HKS.

 

It does seem that people are having more problems with the FelPros, but there were a couple of pretty major guidelines that were not followed here. Namely, not heat cycling the engine and retorquing the head (I generally do this three to four times just to be safe), and then running an unknown calibration at WOT on this fresh, never-been-retorqued gasket. Both bad practices, either of which could easily have been the cause of the problem.

 

I'd look at it this way - yes, replacing the head gasket is a pain, but nowhere near the pain or expense of the broken ring lands that you very likely would have ended up with had the gasket held.

 

Granted, I don't use FelPro head gaskets myself, but I've often wondered how much of their bad rep is simply from the fact that they are FAR more widely available.

 

I'm really not trying to sound harsh here, and I'm sorry you are having problems, but these are pretty important points to understand, and they aren't necessarily obvious.

[Bernardd]

.. Namely' date=' not heat cycling the engine and retorquing the head (I generally do this three to four times just to be safe), and then running an unknown calibration at WOT on this fresh, never-been-retorqued gasket. Both bad practices, either of which could easily have been the cause of the problem.

[/quote']

 

What is the proper way to retorque? Loosen the nuts/bolts, then retorque or just apply the proper torque?

[TimZ]

What is the proper way to retorque? Loosen the nuts/bolts, then retorque or just apply the proper torque?

Let the engine sit overnight, then back off ~1/8 turn, then retorque. I always back off each nut, then retorque it individually. I don't recommend backing them all off at once.

[Thumper]

Also, checking timing with a timing light will only verify that the timing matches the timing marks on the crank pulley. It will not[/b'] verify that the crank pulley is correct.

 

How can you check the timing any other way? When I put the the crank pulley at tdc the cam lobes "look" to be in the positions they are suppost to be. Also I believe when 73turbo240z put his engine together he had the key lined up on the crank snout and the crank timing mark was also lined up on the pulley. So wouldn't this mean the crank timing mark is correct?

[JMortensen]

When building the motor, use a dial indicator on the #1 piston to verify EXACTLY where TDC is. Then use the timing light as normal. Sometimes the rubber ring in the damper comes apart and allows the outer ring with the timing marks to move. So if the car doesn't run unless it has 80º advance, that would be a tip off.

[Guest 73Turbo240z]

When building the motor, use a dial indicator on the #1 piston to verify EXACTLY where TDC is. Then use the timing light as normal. Sometimes the rubber ring in the damper comes apart and allows the outer ring with the timing marks to move. So if the car doesn't run unless it has 80º advance, that would be a tip off.

 

is this instance the crank pulley is an AZ car unit... thus solid state, so it can't "wear out of alignment" it can only be "built wrong"

 

i'll be checking that during disassembly.

[JMortensen]

Then what you would check during assembly is that the pointer on the timing cover actually points to 0º. The pointer can get bent or chewed up and then if it points to 5º ATDC, you wouldn't really know.

 

Personally I don't think that's too big a deal, because you shouldn't really say "I'm going to run xx degrees of timing because xx on the internet says to." Each motor is going to make maximum power at a slightly different spot. You can use what you read here as a guideline, but you shouldn't tune to the internet's specifications, you should tune to your engine's specifications.

[z-ya]

If the timing pointer points to 0 deg + or - a couple of deg when the #1 piston is at TDC, it is not really a big deal. But if the MS thinks that 0 deg TDC is really 10 or 20 deg BTC, that is a serious problem (especially in boosted or high CR applications). I've never seen a L6 timing tab be off more than a degree or two.

 

It's simple to calibrate your timing. It is a requirement on any crank or distributor triggered direct fire ignition system. The distributor trigger systems are not as accurate as a crank triggered setup so it is even more important to calibrate you timing with a timing light.

[TimZ]

Then what you would check during assembly is that the pointer on the timing cover actually points to 0º. The pointer can get bent or chewed up and then if it points to 5º ATDC' date=' you wouldn't really know.

 

Personally I don't think that's too big a deal, because you shouldn't really say "I'm going to run xx degrees of timing because xx on the internet says to." Each motor is going to make maximum power at a slightly different spot. You can use what you read here as a guideline, but you shouldn't tune to the internet's specifications, you should tune to your engine's specifications.[/quote']

 

Agreed. It's far better to tune to exhaust temps and AFRs from a wideband.

[thehelix112]

TimZ,

 

I tune to AFRs and detontation. Wind timing back to whatever doesn't ping, get AFRs right, then wind timing back in slowly until it pings, then back off a touch. Done.

 

Sound reasonable?

 

Dave

[Guest 73Turbo240z]

alright... as of right now...

 

torque was good on the headstud kit... timing was accurate and verified at the crank via the solid state pulley, and using an indicator for TDC on CYL1.

 

head is off, and yes, the headgasket main rings are deformed on a few cyls, pics will follow shortly. I also noticed that between the HKS and this fel-blow that the fel-blow had ports blocked off that the HKS did not, i ran out of daylight to investigate if they are necessary areas or not, i'll be looking into it tommorow.

 

i've decided to skip the HKS 1mm and bite the bullet, and please my credit card companys , and purchase a new 2mm gasket... so far i found it on MSA, does anyone know of other sources for a better deal? i plan on ordering tonight, so the faster the response the better.

[Sean 83ZXT]

http://www.courtesyparts.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=11044-91MM2&Category_Code=s30_nismo_headgasketL28

[Guest 73Turbo240z]

[url']http://www.courtesyparts.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=11044-91MM2&Category_Code=s30_nismo_headgasketL28[/url]

 

ordered from them, skipping swapping to a euro dampner for now i suppose.

[Guest strokerZ]

I think Jim Cook Racing still supplies the HKS 2mm headgasket...thats where I got mine and it was $150.00 last year. Given them a shout.

[zeiss150]

stupid question here... can you re-use an HKS 2mm steel head gasket?

 

I have one on right now and im thinking about changing out my head for P-90 I was just wondering if the steel gasket can be used twice?

 

Just a dumb question.... anyone got a smart answer?

[Guest 73Turbo240z]

stupid question here... can you re-use an HKS 2mm steel head gasket?

 

I have one on right now and im thinking about changing out my head for P-90 I was just wondering if the steel gasket can be used twice?

 

Just a dumb question.... anyone got a smart answer?

 

MSHG's can be reused yes, thats part of there appeal, along w/ part of there cost.

[zeiss150]

Hey 73turbo thanks for the answer.... Sorry to read about all of your head gasket trouble. How much HP were you looking to get out of that bad a$$ engine you built.