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-   -   Help me Diagnose Spark Plugs (http://www.ifsja.org/forums/vb/showthread.php?t=189668)

posulli88 02-26-2021 07:15 PM

Help me Diagnose Spark Plugs
 
Well, I just pulled my spark plugs and I am concerned. I have an amc360 that Rick Jones built to have just under 10:1 compression (I run 91 octane here in Denver). Its run by a Holley Sniper (which I think is probably running a bit too rich). Its a full MSD Ignition system and I probably only have around 400 miles on it total. Between a big move and other projects Ive been working on on the J10 I just havn't been able to drive it as much as I would want. Although I have now buttoned everything up and it's ready to see some miles. You can see the detailed build of the engine here: http://ifsja.org/forums/vb/showthread.php?t=183735

It did bend a push rod (very minimal bend) due to the guy who machined my heads (before it got to Rick) not doing a great job and missing some measurements. Again Rick has been amazing through this entire build and the quality in his work is evident.

Anyway, Ive just pulled the plugs and most of them seem to be fouled. I know reading plugs over images is hard but Ive done my best to capture high quality images below. A couple notes:

I am most concerned with plug/cylinder 1. That cylinder probably hasn't been running because of fouling. Im trying to convince my self its fuel fouled and not oil fouled. It does smell heavily of fuel. Cylinder/plug 2 has 5 minutes run time on it. I replaced it the other day because I noticed the exterior ceramic was cracked and arcing outside the cylinder. I am running NGK FR5 plugs. Also the silver you see on some of the edges of the plugs is anti-sieze from when I pulled them. Thoughts?











Tripwire 02-26-2021 08:03 PM

I think babywag is a FI expert...or was it someone else who helped me some time ago...anyhoo i had two similar issues plugs like yours and plugs that were so fouled in 1 minute it would not run, in both instances it was the TPS, one was mis adjusted the other was wacko and sending WOT fuel when the throttle plates were closed

steve

iapexl8r 02-27-2021 05:23 AM

does your sniper have a afr readout? if not,I would start by making sure that all the plugs are getting spark. you can do this several ways. the easiest way is with an infrared thermometer just use it on the exhaust manifold at each exhaust port while the motor is running and if one is cold it is not firing. verify cap, wire and plug on any cold cyl.

wiley-moeracing 02-27-2021 08:10 AM

Wet with fuel on almost all, looks like weak ignition, otherwise all would be wet if it was over fueling. That is where I would start, then move to fueling.

posulli88 02-27-2021 11:10 AM

Thanks everyone. I will check spark today. The Sniper does have AFR read outs. At cold idle it starts around 13.5 and slowly moves up to around 14.5. I havn't done full adjustments to WOT at all. I will look closer at it.

I set my warm idle to target 14.7. I know sniper is a learning system but know thats not perfect. I might reset the entire system and start fresh.


Will replace all my plugs and take heat measurements at the manifolds.

babywag 02-27-2021 12:39 PM

Few things to consider...
O2 sensor placement.
needs to be as close as possible to engine. Too far away they can become inaccurate.

Must have Zero exhaust leaks!
Even a tiny leak can drastically change reading(s).
Say you have a small leak, o2 reads lean, ecm dumps more fuel to combat inaccurate reading and engine runs too rich.

Is it going closed loop and staying there?

Coolant temp sensor.
Verify it is seeing actual engine temp, and display matches.
An ecm that sees low coolant temps with drastically increase afr.
If sensor is off they will run too rich.

Verify fuel pressure is correct. Too high and injectors dump too much fuel compared to what ecm is expecting.

With efi there is the huge lie/myth of self tuning systems. They ALL need tuning.
Their stock programming is generally too rich for real world imho.
Changing stock values via handheld unit = tuning.

EFI isn't a magic bullet, everything has to be correct just like any carb'd engine.
Spark, good voltage to electronics, etc.

Plugs look rich, but when did you pull them?
Best is to do a normal-ish long drive then pull them.

posulli88 02-27-2021 03:15 PM

Thats super helpful Babywag!

My 02 placement until last weekend when I switched to manifolds from headers (emissions) was on the reducer 2" from the collector (hedman headers). It is now temporarily placed at about 8" past the manifold. Just last weekend I essentially cut the old reducers off and bridged the gap between manifold and the end of the exhaust with part of the old y pipe and a small length of flex exhaust tubing ( I have dual exhaust so cant use original y pipe). The o2 bung is in the solid 2 1/4" y pipe connection on drivers side about 8" back.

I can move the temporary bung closer to the manifold. I am a little confused on O2 placement. I know it needs to be 10 degrees above horizontal but can I mount it in the pipe where the pipe is completely vertical essentially 2" off the pipe flange (2" away from the manifold to flange intersection)?

This is all temporary I will be taking it to an exhaust shop shortly to make a permanent connection from flange to old dual exhaust and to add a cat (again emissions).

I probably pulled plugs at worst time possible. I ran the engine for about 7 minutes last weekend after replacing exhaust and it was cold (35 degrees outside temp). It essentially idled for 7 minutes got the engine temp up to 140 then I pulled the plugs this weekend.

I know fuel pressure is correct I have checked multiple times.

I need to pay closer attention to see if it's going to closed loop and staying.

I believe the coolant temp is accurate on the sniper system. The original jeep gauge also seems to generally match the sniper (I know its hard to tell temp on the original gauge.

Do you think it's worth going through the magic wizard again on the sniper and resetting the system? It was originally set in Massachusetts and I now live in Denver so pretty big difference in altitude. What would you suggest I plug in for target idle AFR and WOT AFR given my engines build?

Thank you!

babywag 02-27-2021 04:59 PM

Quote:

Originally Posted by posulli88
Thats super helpful Babywag!

My 02 placement until last weekend when I switched to manifolds from headers (emissions) was on the reducer 2" from the collector (hedman headers). It is now temporarily placed at about 8" past the manifold. Just last weekend I essentially cut the old reducers off and bridged the gap between manifold and the end of the exhaust with part of the old y pipe and a small length of flex exhaust tubing ( I have dual exhaust so cant use original y pipe). The o2 bung is in the solid 2 1/4" y pipe connection on drivers side about 8" back.

I can move the temporary bung closer to the manifold. I am a little confused on O2 placement. I know it needs to be 10 degrees above horizontal but can I mount it in the pipe where the pipe is completely vertical essentially 2" off the pipe flange (2" away from the manifold to flange intersection)?

This is all temporary I will be taking it to an exhaust shop shortly to make a permanent connection from flange to old dual exhaust and to add a cat (again emissions).

I probably pulled plugs at worst time possible. I ran the engine for about 7 minutes last weekend after replacing exhaust and it was cold (35 degrees outside temp). It essentially idled for 7 minutes got the engine temp up to 140 then I pulled the plugs this weekend.

I know fuel pressure is correct I have checked multiple times.

I need to pay closer attention to see if it's going to closed loop and staying.

I believe the coolant temp is accurate on the sniper system. The original jeep gauge also seems to generally match the sniper (I know its hard to tell temp on the original gauge.

Do you think it's worth going through the magic wizard again on the sniper and resetting the system? It was originally set in Massachusetts and I now live in Denver so pretty big difference in altitude. What would you suggest I plug in for target idle AFR and WOT AFR given my engines build?

Thank you!


Yes...altitude make a HUGE difference!
Whatever it "learned" in MA is waaaay off for Denver. So the fuel maps will be whack until you reset/it relearns.
Makes sense that it'll run far too rich until it relearns.
You need to increase the initial timing by ~7* as well.
Also makes sense that they look like that after only 7mins. run time & 140 temp. that is far from normal operating temp. and not nearly long enough.

posulli88 02-27-2021 08:09 PM

Damn, had no idea on the timing addition. I am at 14 right now I think (ill have to look) so I would need to be at 21 right (or around that)?

For the O2 sensor can it be mounted on a vertical pipe? See below quick sketch. Red is where I want to mount blue is where it currently is. Just confused on the hole 10 degree angle thing.


babywag 02-28-2021 10:01 AM

Stock high altitude initial timing increase is 6-7 degress higher per Jeep. A few high altitude service bulletins were issued stating this.
One states 6 the other 7, so as with any engine what works for one doesn't mean it works for all.
Play with it a little and see what works best for yours.

o2 sensor is probably fine where you have it...the angle they refer to it to prevent cold water/fuel from "shocking" the sensor on cold starts.
Biggest gotchas with them is an incorrect bung. Widebands are picky they need the correct depth to prevent fouling and keep accuracy.

posulli88 02-28-2021 11:15 AM

Thanks Babywag. I have not set up the Sniper to control timing yet. This is my motivation now to be able to do so. Been thinking about buying the Hyperspark system and selling the MSD.

I just went out and measured distance from the Manifold exit to my 02 bung and its 15" if you follow the pipe (I could have sworn I had it clsoer). But it's as close to the verticle section as possible. Unless I put it on the vertical portion of pipe I cant get it closer to the manifold, which I am nervouse about now. I have never really seen an 02 sensor mounted on a vertical portion of pipe. Which is why I was asking the question. I really appreciate your help! Thank you.

iapexl8r 03-01-2021 09:10 AM

iam pretty sure the angeling of the 02 sensor is to prevent condensation collecting on it. you are probably ok on vertical pipe at 90deg

posulli88 03-01-2021 11:19 AM

Talked to Holly this morning. They said I should be ok to put in vertical pipe. It is a bit more susceptible to condensation in a vertical position but I'll get a more accurate reading then being 15" away from the manifold. Apparently on the O2 sensor there is a section where it is a little more shielded so I can have that portion pointing up to provide a bit more protection from condensation.

Ordered the Hyperspark distributor. I can run it with my existing coil and the use the coil driver module that came with the system. (if anyone wants to buy my ready to run MSD Distributor with 400 miles on it let me know haha).

So I should be able to control timing shortly and set this thing up for Colorado (not run crazy rich). I will report back after I get this corrected and see how the plugs are looking.

posulli88 03-02-2021 07:28 PM

ok putting the exhaust back together so I can take it to the shop and have permanent exhaust put in. Is this how the driver connection to the manifold suppose to be?

The problem is the flange doesn't clear the manifold flange so I think its stopping it from fully sealing. The height on the edge of the flange is about an 1/8" taller than the pipe which makes me think its not going to seal up.




should I flip the flange like this:



Or do I need to use a donut in between this instead?


Thanks!

oregonphil 03-02-2021 10:06 PM

posulli88, yes doughnut type on both sides. As a matter of fact my 77SJ is going in tomorrow to get those replaced and a new muffler. Here's a good pic of one:

https://www.fsjjeepparts.com/83300060.html

oregonphil 03-04-2021 06:27 PM

I was wrong, again. I know, can't hardly believe it myself.:rolleyes:

So I checked in on the exhaust shop working on my 77SJ today, and the gasket that goes on the driver's side of the wye pipe, is a doughnut type with a metal insert that centers it into the pipe coming down from the manifold.

The passenger side which has the dampener valve gets no gasket on the bottom with the taper, the tapered side of the valve needs to fit tight and square into that side of the wye pipe. A flat gasket on goes on top of the valve against the pipe flange coming down from the manifold.

At least that's how he's putting together and he has done a lot of 'um.

I have never seen good pictures or a description on this.

posulli88 03-06-2021 08:48 PM

Thanks Oregonphil that was helpful.

So I have a dumb question:

I just got the hyperspark installed and checked static timing. Everything appears to be good to go. I left the radiator cap off during all of this because I just recently added a 190 degree thermostat and wanted to make sure all air was purged from the system. Well the engine heated up pretty quickly. All of a sudden coolant comes pouring out of the open radiator cap. Probably 1 to 1.5 gallons on the floor and engine bay (the fan sent is spraying everywhere) before I could shut the engine down. Huge mess:banghead: I realized I forgot to have the heater running but don't think that would cause this. This has never happened to me before when purging air. When I shut the engine off coolant temp was 180 degrees. What would cause this to happen? I know if it gets too hot coolant can boil over but I thought it needed to be hotter than 180 to do that...

wiley-moeracing 03-07-2021 06:22 AM

You had air trapped in the block and it pushed out the coolant, it happens, especially when you fill to fast. You can leave the thermostat housing off and fill the block full then install and fill the rest of the cooling system or let it sit overnight to purge out air.

babywag 03-07-2021 09:25 AM

I always pull a heater hose when filling these and just loosely attach @angle to core fitting with a gap for air to escape.
works on many vehicles to purge 95% air when refilling.

posulli88 03-22-2021 08:22 PM

Well I have an update. Installed the Holley Hyperspark distributor so I can control timing. I set WOT timing to 34 and the system set cruise at 36 (which by looking at the plugs seems like its a little high) and it seems to be running pretty well. Just pulled the plugs and they are all really clean. Looks like the timing might be a little high as the color change is beyond the bend in the strap?




Thoughts? What would you adjust wot and total to?


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