90 KA24E injector o-rings

[KnightStryke]

Hiya, I'm new to the forum here, which I just found while researching this problem. I've found a few posts regarding the injector o-rings on the KA24E and was wondering if anyone could help me out here.I just got a '90 240 back in July and have been fixing it up as I go. A couple months ago I noticed a gas smell and found the injectors to be leaking from the rail, so I got a set an injector seal kit from Advance (part number 158-0372). The upper and lower seals are fine, but the o-ring going into the rail is too small. It fit the injector snugly, but offered no resistance going into the rail, so it leaked like crazy.Next step, hit Google and found this forum. I sent my injectors to Deatschwerks to be serviced. When they came back I lubed the o-rings and tried again. These were closer than the Advance ones, but still went into the rail a little more firmly but I still had seepage on a couple. After several attempts to re-seat them I had similar results, I could get a few to seal but never all of them. Next I tried Autozone, who gave me GP Sorensen o-rings(part number 800-9209). These were loose on the injectors, but plopped in the rail more snuggly. I still couldn't get all of them to seal again though. After several attempts I contacted a local Nissan dealer who gave me the oem part number. For anyone who may need them the o-ring is part number 16618-78A00, the upper seal is 16636-U5000, and the lower is 16635-78A00. He told me they could order them and have them in four days or that Advance could cross refernce the number. I hit Advance and got the GP Sorensen part number 800-9330, which is supposed to be the same as the oem size. They fit the injector snugly and plop into the rail snugly, but still seep when the engine is running. They don't leak when the engine is shut off and pressure is standing on the system though. What I'm wondering is if anyone has tried the oem part from Nissan(16618-78A00) and if I should spend more money and order them and try them, or is it possible I have another problem? I've inspected the rail and it looks fine, I'm lubricating the o-rings and put them in evenly, they pop in and I can rotate them injector in the rail. Is it possible for the fuel pressure regulator to be bad and allow too much pressure on the rail when the engine is running? Or could it be a vacuum problem? Or do I just need to keep buying o-rings? Thanks for any info, and hopefully these part numbers will save someone out there some cash and wasted time

[neverlift]

WELCOME TO NICO I see you actually have tried on your own and used the magik search function so +2 both for searching before asking,and a half for being newb

ok,the gp sorensen ones worked great they were from napa tho,2 from one store and 2 from another,it was 4 individual kits(one per injector) when you remove and reinstall do the injectors that seal change?,or stay the same?it could be the fpr tho if only happens when car running(pump trying to push 60psi if fpr is gone) I still dont see the problem tho I run at 55+psi no leaks.... thats with a walbro(i've had her to 80 psi and got scared)

[KnightStryke]

Thanks for the welcome The injectors that seal change each time I try to re-seat them, which is what has been confusing me the most. With the 800-9330 I have managed to get them all to seal when the engine is off, and can get two at a time to seal when running, but its never the same ones. I am going to go back out and try again right now just for the sake of it. I have the upper seals(ribbed one) from Advance on at the moment and want to try changing that with the one from Deatchswerks as it is a little taller and firmer. My thinking is maybe it will allow the rail to snug up and hold the injector more firmly. I know, its grasping at straws, but it can't hurt. I'll let you know how it turns out. Thanks for the info on the fpr as well. If by some fluke chance it is the fpr, any recommendations on a replacement? Would it be better to go with just a stock replacement or an aftermarket?

[neverlift]

realy sounds like something is in a bind if they change you know... your not really grasping,if you have the wrong part it kinda is tho.For the fpr not sure how much a stock replacement is but megan adjustable's on ebay for like 20+shipping,had mine(50 from zilvia still megan) for about a year now,still works,came with a gauge and all, they dont send ALL the needed piece for install on the ka(you would need an o ring),but hose clamps,hose and an adapter all included,my next choice would be a mallory(only the fpr tho no nothing else)

good luck

[KnightStryke]

Thanks again for the info. I just tried re-seating them again with the same results. These fit really well compared to the rest of the sets I have tried. They hold once the system is pressurized and turned off, but all develop a seep when the engine is running. It takes about 15 minutes or so to start leaking. I am going to take your advice and look on eBay. For that kind of price I will go ahead and replace the fpr. Once I get one in and installed I will post again and let you know how it went. I will probably go ahead and order the oem o-rings from Nissan as well since it takes a few days to get them in. That way if its the fpr I have a spare set of o-rings on hand and if it isn't the fpr I don't have to wait on the o-rings to come in, and even if the fpr wasn't the problem I will have one less thing to worry about going out in the future. I'll stick the results on here so maybe it can help out anyone else having injectors leaks. All this time under the hood has let me find a few other minor things I need to fix, so at least some good has come of it. And with that I'm off to replace some old belts before they become problems. Appreciate the help

[neverlift]

not a problem.

Yeah those magans are good price and quality(most of their products are good)

you could always check the pressure with a tee and gauge,just to see.... good luck again

[KnightStryke]

Okay, here is the follow up. I got the Megans fpr and installed it. I put everything back together and used the Deatschwerks o-rings I had again(which are the same size as the GP Sorensen 800-9330). Then I nearly fell over when it didn't leak. I've been driving it around for a week now and still no leaks. I've got my fpr set at 45 psi and she's running great now. So now I can start looking into replacing the stock air intake/filter box. Search here I come Thanks for the info Neverlift!

[xs04298]

Okay, here is the follow up. I got the Megans fpr and installed it. I put everything back together and used the Deatschwerks o-rings I had again(which are the same size as the GP Sorensen 800-9330). Then I nearly fell over when it didn't leak. I've been driving it around for a week now and still no leaks. I've got my fpr set at 45 psi and she's running great now. So now I can start looking into replacing the stock air intake/filter box. Search here I come Thanks for the info Neverlift!

Ive been battling the same issue for about a year and a half now with my kae, so im curious what kind of stuff are you putting on the o rings when you installed them, i heard on the grape vine that white grease works the best and thats what ive been trying.

Im pretty sure its not the FPR, it leaks pretty constantly in colder weather, if i even hit the key to turn the pump on without it running they leak (a few of them, quite randomly which )Thanks