Built motor, injectors won't stay sealed?

[05Monsterdmax]

Well over this past winter I built my block. Added dual pumps, had my tips cut, charger etc etc. all the valve covers were powder coated. All mating surfaces were sanded down to ensure the injectors were sitting down in the bore far enough. Swapped the oem injector hold down bolts out to a harder grade and are getting torqued at 35ftlb vs the stock 22lb or whatever it was. When u really beat down on it the injectors still seep fuel out. This is only on my 600hp tune, not any of my big ones which would really pour prolly. Idk wat else could be the issue unless the oem hold Down retainers are flexing and letting the injector raise under high pressure. Are most of u guys with built motors/dual fuelers etc running billet tie downs or the existing oem ones? I've done everything I can think of and still to no avail..

 

[Hot COCOAL]

I read in Brian's thread "well I guess it's time" the other night , he was torquing his aftermarket bolts down to 65ft lbs based on input from another member, maybe 35 is not enough, maybe the tips are not perfectly conical, or maybe as you stated, the hold downs are flexing, I think so cal makes stronger ones....

Sucks man, good luck figuring it out

 

[Hot COCOAL]

I quoted and pulled up the specs on the hold down bolts in a post on brians thread(hondarider552)they were the so cal studs, and they were needing 65ft lbs

I am computer ignorant, and don't know how to copy and paste the link, sorry

 

[05Monsterdmax]

Hmm not certain. 65lbs I feel as if they will break cause 35 is stout on just a 12mm bolt or whatever size it is. I'm outta ideas minus socals billet retainers.

 

[Hot COCOAL]

???
Idk anything

 

[05Monsterdmax]

Where did ya search to find his thread about them arp bolts? That may be an idea as these I got helped alot gaining that extra 13ftlb, but still not enough but I was nervous they was gonna snap. Appreciate the help though Forsure. Shits been bugging me non stop lol

 

[Hot COCOAL]

It on today's posts three topics down or so, in hondarider552 thread called I guess it's time, I quoted the specs posted from earlier in the thread and posted em just a few minutes ago:hug:

Best I got

Lol

 

[mackthehack]

What brand hold downs did you use? They didn't come with torque specs? Are they torque to yield?

 

[mackthehack]

Here you go. http://www.duramaxdiesels.com/forum/showthread.php?t=45590&page=49

Post #728-730.

 

[05Monsterdmax]

They are just my factory hold downs that came on the lly. Idk if people are running them or replacing them with stronger, but I know mine keep leaking under wot. I just looked up socals retainer kit, $650 bucks didn't see that one coming. Lol they come with bolts also but are only torqued to 32lbs it says.

 

[mackthehack]

I would spend the money for a piece of mind and not have problems.

 

[05Monsterdmax]

That idea is fine even though they are lil pricey, but I'd like confirmation before I spend 700 bucks that'll it'll keep them down. If not ill prolly set fire to it and buy me a lml lmao.

 

[mackthehack]

That idea is fine even though they are lil pricey, but I'd like confirmation before I spend 700 bucks that'll it'll keep them down. If not ill prolly set fire to it and buy me a lml lmao.

Try calling Guy @ SoCal tomorrow for confirmation.

 

[05Monsterdmax]

Yeah that's the same thing I was thinking. Ill give him a ring in the am and prolly newly to see if either has ran into this issue before.

 

[Harbin_22]

This is not a common problem especially at the power level your at. What do you mean by them leaking fuel out. Like where from? If you command the rail pressure up at idle, does it leak? Or is it just under load? You shouldn't be pushing hold downs up at 600 HP.

 

[05Monsterdmax]

Comes out of the bore like the injectors are lifting and its passing by the copper sealing washer. Does not leak a drop at idle or regular cruising, just wide open throttle. I've pulled them and resealed them several times, still the same result. From the research I've been doing last few days most high hp trucks are running billet retainers.

 

[THEFERMANATOR]

How high are you running your rail pressure? There has been a few LLY injectors that leak fuel out of the body under high rail pressure. Make sure your rail pressure sensor is rescaled if you are running over 180 for rail pressure. Other wise once it hits 180 it will just keep climbing and make them leak.

 

[05Monsterdmax]

Ill have to look. Kory at power performance tuned it.

 

[Wildman]

You are not lifting and/or not seating the injector. It is 22 ft lbs on the hold down bolts btw iirc. I had this same issue when I took my injectors out to clean the nozzles. I chased this for a month without answers from anyone before I figured out my issue. I had fuel seaping out the injector cups after a hard pull and it would run down the cylinder head and burn till i smelt it. Long story short after numerous orings and new copper washers I realized neither of those keep the fuel in the injector. If a copper washer leaks you'll know it's very audible sounds like an air compressor nozzle when it hits due to the compression leak. The orings are just to keep dirt out of the hole. SO what happened was my nozzles were not seating to the injector body itself and it would leak around the threads. You have to take the nozzles off clean them well and torque them on the injector to 65 ft lbs iirc then i would crack them loose a tad and re torque them to 65 ft lbs and go an extra 1/8th turn to seat the taper seat on the nozzle and good as new problem solved. No more leaks. This drove me insane for 5 weeks the truck would shake under load and have a loss of power. Hope this helps in your case

 

[dirty_max]

You are not lifting and/or not seating the injector. It is 22 ft lbs on the hold down bolts btw iirc. I had this same issue when I took my injectors out to clean the nozzles. I chased this for a month without answers from anyone before I figured out my issue. I had fuel seaping out the injector cups after a hard pull and it would run down the cylinder head and burn till i smelt it. Long story short after numerous orings and new copper washers I realized neither of those keep the fuel in the injector. If a copper washer leaks you'll know it's very audible sounds like an air compressor nozzle when it hits due to the compression leak. The orings are just to keep dirt out of the hole. SO what happened was my nozzles were not seating to the injector body itself and it would leak around the threads. You have to take the nozzles off clean them well and torque them on the injector to 65 ft lbs iirc then i would crack them loose a tad and re torque them to 65 ft lbs and go an extra 1/8th turn to seat the taper seat on the nozzle and good as new problem solved. No more leaks. This drove me insane for 5 weeks the truck would shake under load and have a loss of power. Hope this helps in your case

lly does not have cups. to the op, it sounds like you are pushing fuel past the check ball, the only fuel in or out of the injector is from the hard line on the side, the return line out of the top, or obviously into the cylinder. it is highly unlikely that it is being blown back out of the cylinder, past the copper washer, and past the oring seal. if it looks like it is coming back up through the hole, it is most likely that check ball because rail pressure is too high