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Author Topic:   #3 and #5 plug melted Help!!
dirtracer14
Member
posted August 01, 2004 12:33 PM
I really need some help here before i lose this motor for good. I have gone up 12 jets sizes from what i started at wich the motor ran fine for 6 nights on a dry track. Last night was the 3rd time with #3 and #5. I went up 12 jets and double checked the float level cleaned carb ..new gaskets went up a tad on fuel pressure (kse with 3 1/2 idle and 8 to 9 end of straights with about 6 coming off the turns) I made it threw the heat and the dash then a few laps in to the main i heard it drop a hole and pulled off and found the electrode gone on 3 and 5. The last 2 times it went it was right after a caution when we would go back racing i would here it. I will try and describe the car its a short 4 bar lr and long wishbone rr..The car is up all the way around the track and has some awsome side bite wich stands the car up on the right side real hard...about 1' under the lf with the rf down and the lr up and this is most the way around the track except for a quick set for the turns then back in it. I am wondering am i running the left side out of fuel from to much angle in the car and the g force. The right side looks pretty good but not looking brown. The other thing was that when i jetted up i started to get allky in the fuel??? But i also went up on the kse pressure...is the pill for idle or wot. The timing is at 34 with msd dist and msd 8 mm wires. I really need to get some help here i cant afford to lose this motor!


NJantz
Member
posted August 01, 2004 04:04 PM
Yep its new msd with hei type cap.


outlawstock17
Member
posted August 01, 2004 04:52 PM
are you losing any water? have you had the left side head off yet? i would start by pulling the head and having a look see...


dirtracer14
Member
posted August 01, 2004 04:57 PM
I have had the head off 2 times and 2 diff heads i will try and load a few pics of it if i can or email to someone that can.


outlawstock17
Member
posted August 01, 2004 04:59 PM
just read your other post about the blown head gasket. your problem sounds like it is a low spot in the block between the 2 cylinders in question.....commonly known as "torching the block".


dirtracer14
Member
posted August 01, 2004 05:09 PM
Both the head and block are flat ...just had the head gasket off and checked befor i put it back on. I also have done sevaral comp checks that come up at 200 each side. I have some really good pics of the plugs but cannot get em loaded on here. The temp was down about 180ish and i did notice on a caution the the temp went up to about 190 then dropped back to 170 and then stayed there...i have a 160 t stat in it and not losing any water.
The other post about the head gasket was my mistake in the way i put the head and intake on. The first time the plug burnt it appeared as the valve broke causing the plug to burn but did not hurt the head gasket then...at the time i thought the valve caused it but now after burning the same plug 2 more time i would say the first time it burnt the plug then i kept running it and burnt the valve...also cracked the head.

[This message has been edited by dirtracer14 (edited August 01, 2004).]

Dustejr73
Member
posted August 01, 2004 09:58 PM
I run the kse pumps....i think that i am running out one side of the bowl or getting it to such a low level that when i hit the turn it will get some air. I also took the carb off and took a look at the intake and the runners for #3 and #5 come right up to the top of the intake with not much spread for both runners to feed from? I might change back from the super vic to the Jr or maybe a spacer to give more plenum room befor it hits the runner..

You will never see me at SoS again atleast till allot of things get changed....like condition of the surface i was down in june and only had 4 wheels on the track when we were coming on the track...the rest of the time it seemed like i only had 1 wheel on the track...plus beat the **** out of my elbos on the seat!!

dirtracer14
Member
posted August 08, 2004 11:34 AM
well another night and another burnt #5 only this time. I made a tilted spacer to help keep the fuel on the left side of the carb.... i think it helped some. When hot lapping...bad fast tacky drive it in hard and drop the hammer kind of hot laps....about 15 laps. Came in pulled #3 and #5 and 5 was gone again. Put new plug in and was gonna take it easy in the heat and check again....ran heat and the track was slicked off but pretty good bite still came in no problem. Go out for the dash same thing slicked off and no burnt plug. For the main the track was locked down taking good rubber just a tad slick off turns...ran 30 laps with only 2 yellows and checked the plugs no problem???? What is going on here is it just leaning the left side on the top end?? The right side plugs have good color and the left are still looking new? I think i am getting close just affraid to twist it up...i would like to add some gear to get more rpm but i need to get this plug issue fixed first..


dluna
Member
posted August 09, 2004 07:29 AM
14 -

You seem to be having a VERY expensive problem!!!

We have had close to the same thing happen 3 different times this year.

1st - engine builder thought it was the alcohol we were using. switched to a new supplier at the begginning of the year and burnt #3 and #5, taking a chunk out of the head and block at the same time.

2nd and 3rd time both seem to have been because of the plugs. New engine and we have never had problems with heat. Engine would run really hot. Turns out, I bought 2 sets of plugs from the local part store and they must have gave me the wrong ones that I asked for. Both times, the electrodes were gone also. Rebuilt engine and put the correct plugs in, no problems in 2 races thus far.

I'm sure either of these are not the cause, just wanted to throw them out there just in case.

GOOD LUCK!



merlinmech2
Member
posted August 09, 2004 07:44 AM
had a bad dist. do that one time. also cooked the piston tho. mag pickup was cracked and timing would go crazy above 5700. never used to get it that high when setting timing before. I have never seen plug come apart with a lean motor, only timing. just something else to look at. good luck.


dirtracer14
Member
posted August 09, 2004 07:52 PM
I am seeking any help with this ...it really could get allot more spendy if i dont find the problem. I was gonna drop down a temp range on 3 and 5 to see if that would help. I have changed dist and double checked TDC and made sure the balancer didnt slip(i mark em new now). I know that as i have been adding more jet i am getting longer before it goes and the tilted spacer helped. This motor should flow VERY well on the top end more than any other motor i have had. I have tried sets of plugs from dif stores just incase a bad bunch... The other thing i was thinking is maybe the cam overlap or somthing...maybe to tight lash...i dont know i wish it would just go away!!


awkwardjeff
Member
posted August 09, 2004 10:22 PM
14, You still having that problem?? The only time I have seen the plug end get melted off is for one of two reasons.... timing...... and you have that covered.
The other is too much oil in the chamber with a LEAN hole.....

I still feel you are pulling air/oil from inside the valley of the motor, this will cause a blow-torch and the oil fouls the plug so now it melts the plug.

You are trying everything you can to compensate for the problem.......you are doing such a good job you believe you are headed in the right direction even.....

You wonder WHY on a heavy track and not on a dry track..........you are NOT creating enough s-u-cking to pull oil past the intake/head area on a dry track....... You almost addmit this is the problem by saying you want to fix the problem before turning more RPM's.......

if you could put a bigger CFM carb on the motor to allow more air/fuel into the motor it wouldn't try sooo hard to pull oil past the intake gasket.

You have this motor on kill, lots of compression, lots of overlap in the cam, and all this is s-ucking the intake gaskets in, because those two cylinders are on the hot and lean side to start with they will show the problem first.......

Has this block ever been burned on the deck? You stated it was checked and is flat........the finish on the deck is cut in a way to hold the gasket......and you stated that both cylinders had 200 psi of compression.....I assume you checked AFTER it burnt a plug and were checking to see if the head gasket got torched??? how about backing off the intake valves, and use a motor lifting plate with a pipe thread plug welded in to either put pressure in the intake or better yet use a hand pump to create a vacume in the intake to see if that leaks?????

I edit this message only to add this thought....... years ago I bought a used intake and had the problem you are having......... the intake was cracked, someone pried it off with a crow-bar instead of cutting the silicon on the ends they just pried it up until it cracked.....they went broke building motors always using the same intake....changed carbs, ing., and tried everyting........ I was like you......I stayed on top the problem and figured it out.......... I welded up the crack and still use the same intake I bought when they went broke and quit racing. I forgot about that until I re-read what I originaly posted.

So YES.......back off the intake vavles and vacume test the intake.

[This message has been edited by awkwardjeff (edited August 09, 2004).]

dirtracer14
Member
posted August 09, 2004 10:35 PM
I really think you have me headed in the right direction....i went andf pulled the carb again and looked down the intake.....sure enough there is oil around the mating surface....i assume that the oil/air are coming in together on the top end. Do you think a 780 is to small? Do i change the intake to one that is not ported as much? How can i seal the intake? I glued it down real good last time with silicone. Would the oil work as a detonation factor allom preignition? I wont be able to sleep with this new found problem...but defenetly needs to be addessed before dumping a ton more fuel to compensate.Back to the shop for now!!


dirtracer14
Member
posted August 09, 2004 11:02 PM
Ok how do i get the intake to seal? Is it ported to much...i have some stuff called high tack that my dad use to to seal his intakes? should i use that....its like glue and will allmost not come off of steal...I also have a intake that is only ported to the 1206..should i use it? Jeff you might get a early X-mas gift


awkwardjeff
Member
posted August 10, 2004 08:24 AM
14, I gotta get to work this morning so I only have time to write a short answer.

Get yourself a felpro 1266 intake gasket set, they are the same port as 1206 but are twice as thick........this will help if the angle is off, or if the intake is bottoming out on the block......... ALWAYS use high-tack, NOT silicon on the intake/head gaskets. ONLY use silicon on the ends of the intake to seal the block.

Also......ported too much.......are they ported so the vavle cover stud is showing in the intake runners???? I had a set one time that were that way.......vavle cover stud came loose and it melted pistons because of s-ucking are down the threads of the vavle cover stud......stud didn't fall out either, just loose......that was one of them on kill motors you got........it take VERY LITTLE to kill the thing....

I'll check back tonight when I get home, check your PM here also

dirtracer14
Member
posted August 10, 2004 10:14 PM
Well after pulling the intake off....all the ports had oil in them.. The gasket was good and stuck to the heads but not at the bottom of the runners?? Most of the silicone was gone from the mate surface on the intake side...didnt stick to the gasket. I will be picking up a 1266 set and high tacking them back on this time. In the past we have never had to seal the intake side of the gaskets but we would set it on snug it up and let it sit over night then tighten the rest of the way...is that a good idea with the high tack? Or just tighten em up? The other note since it appears to be thew gremlin i am gonna take the tilt spacer off......


awkwardjeff
Member
posted August 11, 2004 01:13 AM
14, it's 2am local time for me and I just got home from work, sorry I missed your call.

we will talk in depth when you call tonight, but I would think the ported intake will work fine with the 1266 intake gaskets.

I tack them to the head, I use the spray can tack......I let it set up for a minute or two while I apply silicone to the ends of the block, when the tack is sticky.....it goes on wet, it tacks up in a few minutes...then I apply the intake gaskets to the head......then drop the intake in place. I don't tack the intake side of the gasket...... But I do drop a distributor in place to help locate the intake on a set of head like you got.......1/8 inch aint much so getting it located correctly is IMPORTANT. then torque in place starting in the center and working side to side then out the the ends.......

You may have a hard time getting 1266 gaskets.....they seem to be special order deals and NOT on every felpro list, I promise they do make them......

You stated the gasket was stuck to the head good but not at the bottom......sounds like the ANGLE is off......the heads are angle milled and the intake didn't get perfect. This is WHY they make the 1266 gaskets.... you have good CRUSH holding the top of the gasket and no crush holding the bottom, by adding thicker gaskets you will get much more crush on the bottom of the gasket to hold it in place....... does that make sense??

[This message has been edited by awkwardjeff (edited August 11, 2004).]

ryan
Member
posted August 11, 2004 06:09 PM
We always use blue silcone on the ends and around the water ports. We use yellow weatherstrip adhesive around the ports. We had intake sealing issues until we switched to that method.


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