johndinu

...as opposed to their instructions...
should I yank em out?
what are the implications? could sit too high into the manifold and not spray properly? or could they leak?
I could see that the lower square section o-ring may not seat deep enough and may leak because of the taper...

PS: That's South Bay

southbay08

The complaints that we have received throughout the years with the bosch lll's is that fuel leaks from up top if the injectors are installed into the rail first and that's an installation or an oring issue. We have found that when they are installed into the intake first it alleviates all leakage from the rail side, has to do with alignment. The reason why the oring is square is that we have them custom made for our adapter and for proper fitment. When we first designed the adapter for the bottom of the injector we did R&D for about 6 months to make sure fitment was perfect before we started selling them. They are specific for the adapters and yes you are correct, they don't sit as far down into the intake as the stock, but it is ok. Guarantee you will not have a vacuum leak. Will tell you that the injectors will more than likely leak if they are not installed properly.

johndinu

ok thanks for the quick reply.
wondering if I cycle the fuel pump it should be obvious if they leak. if they don't leak now, could they leak maybe later?
I ask because I bolted the whole thing back up. if there is a risk for future leaks even if at first they don\t I\d rather take the fuel rail apart and install again
thanks again for the awesome support

southbay08

No thanks necessary, we are here to help. If they don't leak once you pressurize, then they will not leak later on. It will just mean that they were actually aligned properly and you will be good to go. If you have any problems please don't hesitate to give us a shout.!

johndinu

I see...
decided however to take em off after all. tried to push down on em a little and 2 front ones would go down and stay there, 2 rears would spring back up. so I don't trust they're properly aligned.
I'll just reinstall as per your recommendation. (after all the note is written in red on the website)
in retrospect good thing I did, while losening up the runner bolts I noticed one was lose the whole base runner plenum contraption is pretty intricate and with new gaskets it's easy to end up with lose bolts as u finish up the instalation.
thanks again for the awsome help... will post back with a nice burnout

southbay08

my pleasure....please keep us posted!

roger55

I thought I would tag along on this thread. I was going to try and fire my engine for the first time today but the D3 injectors leak. I don't know how many leaked but it looked like 2 or 3.

I bought these injectors from you last August on ebay and installed them on my engine when it was out of the car that I've been working on. It's a '91 305 TPI and I got the 19lb Bosch injectors from you on ebay. It was last August when I bought and installed them but it was just today that I was going to fire the engine for the first time.

So, I just pulled the fuel rails and took out the injectors. I had a heck of a time getting them out of the fuel rails. I put a little oil on them and let it sit for a few minutes and then I was able to get them out. The orings still seem very stiff though.

I want to get new orings (at least for the top) and give it another try but I have an issue I need you to look at. One of the little oring retainers broke when I removed the injector and another one cracked. The other 6 look OK though.

Here's the one that broke:



So my questions are:

Can I use these 2 injectors with the retainer broken or am I going to need to send them back to you?

I suppose I could get new orings for the top here locally as it looks like they are the same as the OEM. But I'm not sure if I should re-use the bottom orings or not. They seem pliable and undamaged. If I should replace these too, where can I get them? What application are they?

Looking forward to your reply. I'm anxious to get this engine going.

johndinu

sorry hear about your misfortune.
just to say that I have used dishwasher detergent and installed first into the manifold. then placed the rails over them and finished by tightening the 4 bolts equally.
If the square bottom orings are not cut I\d reuse them.
disconnect and plug the vacuum line (and nipple) from the fp regulator, then start the car and let idle. if they won't leak then they'll never leak
g/l!

roger55

Thanks John. I think you are right about the square bottom orings. I think they will be fine. I just picked up a set of new Fel Pro orings for the top. I'm also thinking that the damaged retainers will still work for holding the orings in place so I'm tempted to try and put it back together.

I want to wait for SouthBay to respond before I do anything though.

johndinu

heard the top ones from the dealer are meatier. have not seen side by side...
in my simple mind if u miss that lip maybe when u pull em out again the oring will remain behind. but can't see em leaking because that

roger55

I agree. I think they will work fine but I'd still like confirmation from SouthBay.
I almost decided to put it together this afternoon but thought I should wait.

I did put the orings side-to-side and the Fel Pro look the same as the others.

Btw, I did install the injectors in the rails first. It just seemed intuitive to do it that way. I should have done what the instructions said.

johndinu

lol did the same first time thing is I got together with a buddy when ordered and got 2 sets in the same package. gave him the instructions...
I am not implying they will leak with the felpros.
don't worry he'll answer. it is sunday evening tho
g/l!!

southbay08

Hey guys sorry for the late response. Just got in from NJ. went to Summer Slam at Englishtown, About the orings, you are correct in that without the oring retainer on top, when you go to remove the injector the oring will probably stay in the rail but will not cause it to leak. The felpro orings may fit a little tighter just be careful you don't shave them putting them in. The rail is pretty sharp. If you want just give me a call at the shop and I'll be more then happy to send you some. I can also replace the retainer for you if it makes you more comfortable no problem.

Frank

roger55

Thanks Frank!

I put one of the Fel Pro orings on and test fit it in the rail using a little vaseline and it seemed to slip in easily. So, I think the Fel Pros will work just fine.

No big deal at all if all the retainer does is not let the orings slip off when removed. I won't worry about that and just put it together tomorrow. I'll do it like I should have in the first place and put them in the manifold first.

I'll report back tomorrow and hopefully it will be with good news.

Thanks again and I hope you had a good day at the track.

Roger

roger55

Success! No leaks and got the engine started for the first time for me. I got it timed and ran it for a while. The vehicle isn't drivable yet as the brakes aren't on it yet.

It runs great! Really idles smooth. I've had 3 TPI cars before this and this one seems to idle better than those did.
Hey Frank, do these Bosch Injectors give you a better idle???

Btw, I bought this engine a year and half ago. It was a fresh take-out of a '91 Camaro with 63K miles. I've put it in my '57 pickup that I'm doing a restomod on. I cleaned it up and put some Chevy Orange paint on it.

Here it is when I got it, cleaned up on the stand and in the pickup:

johndinu

ddamn... u could eat off of it!

southbay08

Damm that's a clean machine,,,,. Word has it the Bosch 3's idle the best of any injector. Once you get her on the road, you should notice an improvement in throttle response also, Post or send me some pic's of your progress and let us know how she runs. Good luck with her

Frank
https://www.facebook.com/photo.php?f...type=1&theater

alex722607

iTrader: (3)

So I got Bosch III injectors from sfi last month and installed them. However I think I opened a kettle of fish that should have stayed closed. First, I managed to break two bolts, one of which was one of the fuel rail bolts ... God I hate this intake.... Then the Cold start injector started leaking .... lost about 5 gallons of gas from the rear of the rail, thanks GM... and I am on my second set of gaskets for my plenum and runners, and it seems like a third is on my horizon.

So I need some help, I have two possible fault points that I can think of:

1. I installed my second set of gaskets wrong
2. My injector wiring is screwing with me (rats chewed it up about 12 years ago, and it was soldered back together, I am installing pigtails tomorrow on the bad ones.

The car is: hard to start and keep running. When given gas in park/nuetral, wants to die and does not want to rev up. Feels like an entire bank is not firing, and both of my fuses for the banks are good. Under load, meaning in gear, it is impossible to keep running.


Tomorrow I plan to try the following and suggestions are greatly welcomed:

Disconnect 1 injector at a time then start engine and note any differences
spray chemtool on the intake plenum and runners ... again ... and note any changes.

One thing I noticed today: When the car went from 305 to 350, the only thing that changed was the block, nothing else. Recently I changed to an 89 5.7 prom (deleting the CSI from programming, but not from existence), and that's it. I read on here that the ESC is different for the 5.0 and 5.7. Sure enough when I looked it up, the part number is different as is the price. Also, I have been running the 89 prom for three months with leaky injectors (prior to acquiring Bosch III's) and the only thing that happened was the occasional stall.

Every time I pull the plenum, it seems like another problem happens (I don't smell rotten eggs after the last time I pulled and reassembled the plenum, or maybe I just got used to it)

I haven't been able to drive the car for a month now, and I am very close to ditching TPI

HELP please...
and sorry for stealing the thread

johndinu

use a 12v led as a noid light to check for juice at the injector connector
manifold leak (like when u forget to plug a hose) should not affect that badly.
good luck!

alex722607

iTrader: (3)

thanks for the response:
yea I'm tackling the injector connectors tomorrow and if all else fails I will use that method. The vacuum leak, is more of like the gaskets not sealing properly. And I hope its not that.

alex722607

iTrader: (3)

Well low and behold, I replaced my faulty wires after unplugging each fuel injector and noting any differences ( there were none). Runs okay now, but could be better. All are firing but I have an unsteady idle which I can deal with for now I guess. It could be the wrong esc or timing is wrong. I don't smell anything weird from the tail pipe and haven't heard any backfiring as of yet. Once I gigot a longer ride I will know for sure. Thank you for suggestions John, glad I didn't pull the plenum again.

johndinu

u're welcome and welcome to the club.
me too I think idle could be smoother but I only want to lay some rubber down

johndinu

UPDATE:
may have been old gas but idle really cleaned up
hit the strip and got 15s even @92mph on a very hot day.
fuel mileage improved too. old inj must have been leaking like crazy. avg 21+mpg (80% hwy gently driven).
runs better than it ever ran... ty so much Southbay!