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79 Eldorado - Fuel Injectors

Started by Jaks79Britz, August 13, 2022, 04:35:15 PM

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Jaks79Britz

I've been working on my 79 Eldorado and was wondering if anyone has used the new ACDELCO fuel injectors to replace original ones?   I removed them to inspect for contamination or damage and I feel after doing all that work......Why not just replace them if I can get them new?  Besides from throwing money at the parts, has anyone had a bad experience with the new ones available?

Another challenge I have with the originals is that I cannot take of the plastic cover on the injector tip as indicated to do in the blue and white fuel injector book before cleaning. It says to remove the plastic caps with a flat nose pliers and gently twist and pull.  I can get them to turn but cannot pull them off even while applying lots of pressure.  I notice on the new injectors, they don't have the plastic caps.   

79 Eldorado Biarritz
79 Coupe Deville

79 Eldorado

#1
Jack,
You are ahead of me but I'm doing my seals now as well. I cannot answer your question about the end piece. I did come across a place called The Injector Shop and their testing /cleaning service is reasonable. I also saw that the Standard Motor injectors are $26 and change on RockAuto

Here's a link to the service page of The Injector Shop:
https://theinjectorshop.com/collections/fuel-injector-cleaning-and-flow-testing

I also saw a quick video where someone was cleaning with brake cleaner and using a tire valve stem with core removed as the interface.
https://www.youtube.com/watch?v=ed1tMS66-zo

Scott
EDIT: Jack after reading some info on a fuel injection site I now think it's probably not a good idea to try the cleaning procedure which I added the link for. Here's the source and what they say:
https://www.injectorrx.com/fuel-injector-cleaning-and-flow-testing-service/fuel-injector-cleaning/diy-fuel-injector-cleaning/
"DIY Fuel Injector Cleaning at Home

Cleaning fuel injectors by soaking them in, or flushing them with carb and or brake cleaner does absolute nothing. It might flush out "some" loose dirt and grime but, that's about all. If, as suggested in some of the YouTube videos, you start the DIY fuel injector cleaning process at the inlet side of the fuel injector there is a very good chance to lodge loose dirt and grime between the pintle and pintle sleeve.

100% of fuel injectors we have tested after they were cleaned via a DIY fuel injector cleaning project failed the minimum acceptable performance standard for that specific fuel injector."

Jaks79Britz

Hi Scott,

I ended up buying new ACDelco injectors from Rock Auto instead of cleaning the old ones.  For the life of me I couldn't get the black plastic covers off and I didn't trust cleaning them as it indicates in the service manual with them on.   I just received the new injectors yesterday and they don't look identical to the originals.  The bottom of the new injectors are shorter and you can see in the image do not have the black plastic cover.  I see that they sell them on the fuel injector site you linked, but I would think that they would've come with the new injectors.  The new ones came with both o-rings for each injector.

The ACDelco part number is 217-3453 and I cross referenced other websites to assure they were the correct ones for the 79.   I haven't been able to get a response from other owners who've used these new injectors and could vouch for them.

79 Eldorado Biarritz
79 Coupe Deville

Jaks79Britz

Update.  I was finally able to get the black plastic covers off, but I pretty much had to destroy them to remove.  I only did this because I found that I can get new plastic covers on the fuel injector shop:  https://theinjectorshop.com/products/denso-fuel-injector-pintle-caps

I also noticed that the tips are completely different and it appears that the new injectors are missing an insert with the little pin as seen in the image below.  Either that or the new injectors could have a completely new design.  If this is the case, how do they perform compared to the originals?  Is it worth having the original sent out for cleaning?   I'm not going install the fuel rail this weekend after all because I have more questions to answer.  I'm going to call that fuel injector shop to see if they're familiar with the new injector design.   I'll keep you all posted!
79 Eldorado Biarritz
79 Coupe Deville

79 Eldorado

Jack,
When I saw the Standard Motors injectors about a year ago I bought some and they have the same tip as you AC Delco version. They are as well missing the cap. I would have suspected the caps would be by BOSCH or advertised to fit BOSCH. I think our injectors are referred to as BOSCH "Jetronic" and our electrical connections EV1.

The Injector Shop has been very responsive. I'm thinking of sending my originals to them. I planned to install the Standard Motors injectors and have the originals rebuilt and on the shelf but when I saw they had no caps and the design was different it meant I needed to at least get caps.

Scott

Jaks79Britz

Scott,

Just to clarify...you bought the Standard Motors injectors a year ago, but have yet to install them?   Given they have the same tips as the AC Delco I bought, are they not ready to be installed as is? 

I tried placing a plastic cap that came off the Bosche on the AC Delco and it doesn't fit.  The O-Rings fit just fine with out the caps.
79 Eldorado Biarritz
79 Coupe Deville

79 Eldorado

Interesting. Honestly I don't know. These are the first fuel injectors I've removed and really looked at. If the seals fit then I suspect you are correct that they don't use an additional cap. When I saw mine had no plastic cap I thought about comparing measurements but I got carried away with other things and didn't do it. Your photo seems to answer the question though.

I also took a look at the Denso cap and the BOSCH and visually the Denso cap does look correct.

Based on your test fit maybe I'll go back to plan A and use the Standard Motors parts. It would be good to hear from someone who knows the new injectors better though. The Injector Shop is very responsive. I would love to put my car together sooner than later.

Scott

bcroe

Half a decade ago I was swapping several 79 E
injectors, I think the new ones had a metal tip
the same dia as the plastic, fit the same.  I
was just as happy to get rid of some plastic,
but did no more research. 

A replacement injector needs to physically fit,
have the same flow rate (39 lb/hr for the green),
and have the same peak and hold low impedance
drive requirement.  I suppose the same spray
pattern would be best.  Bruce Roe

79 Eldorado

#8
Bruce,
Some of the replacements even have the green colored connector. I know the color doesn't magically change the parameters but it does seem to say they knew what they were copying. As I recall ironically the AC Delco version was the only version pictured without green somehow incorporated. The Standard Motor injectors have a green band around the mid-section and the Ultra-Power have a green electrical plug like the originals had. The Standard Motors parts I bought around a year ago have no such green band/stripe.

This site, Injector Rx, has a diagram which shows what the injector spray should look like. It wasn't what I pictured. They did a nice test with dyno and MPG results using some home brew methods. The high pressure cleaning method blew apart some of the filter baskets into the injectors. I guess I could rig something to test them but after seeing what it costs to send them out and have them cleaned and tested I think I'll use the replacements and I'll send the originals out for cleaning (why?... not really sure but it feels like some of this stuff is preserving history). I plan to send my to The Injector Shop just because they have been so responsive in communication.
https://www.injectorrx.com/fuel-injector-cleaning-and-flow-testing-service/fuel-injector-cleaning/diy-fuel-injector-cleaning/

My car ran well and I was surprised but all of the injector seals seemed to still be in good shape. I have no idea of the history before I bought the car other than it was a central Texas car and with one owner since around 1980 or 1981 (second owner though). I could tell that one of the brackets had been repaired so I strongly suspect someone had the injectors out previously and probably to do the seals; all just assumption.

Scott
Edit: Here's the direct link to the Injector Rx testing article I mentioned:

https://www.injectorrx.com/fuel-injector-cleaning-and-flow-testing-service/fuel-injector-cleaning/injector-cleaning-methods/

Jaks79Britz

B
Quote from: bcroe on August 20, 2022, 10:34:35 PMA replacement injector needs to physically fit,
have the same flow rate (39 lb/hr for the green),
and have the same peak and hold low impedance
drive requirement.

Bruce - when you were replacing with new injectors were they plug and play? Or did you need to test them for the flow rate you mention above.   I couldn't find any detailed specs on the AC Delco injectors that tell me the flow rate.
79 Eldorado Biarritz
79 Coupe Deville

bcroe

I do not have a setup for testing injectors, I
just install them like everyone else.  Then I can
look at my Wide Band OX sensor to see if fuel is
about right. 

I did buy some equipment and test fluid, but it
sits waiting for me to adapt it to fit my injectors. 
Bruce Roe

79 Eldorado

Jack,
They must be the correct flow rate else the replacements wouldn't be valid replacements. That said I have encountered what seems to be more than my share of incorrect parts but I think these replacements are going to work.

I'm really struggling getting my fuel inlet flare fitting removed. Long story but I cut the line to remove the manifold. I tried heating it tonight and it still won't budge. I tried a second time; still no luck. I'm almost out of tricks. I'm mentioning that because it may mean you will get yours together faster than I will.

Scott

Jaks79Britz

Scott - are you referring to the fuel line connector into the fuel rail in near the distributor?  If so, then I had a hard time too.   I had to remove the rail with that connected and then used vise-grips and a wrench to get it loose.

I installed the new injectors on the rail and test fitted them into the manifold. It all fits nice and snug now.   
79 Eldorado Biarritz
79 Coupe Deville

79 Eldorado

Yes. The fuel supply line near the distributor. I cannot even remove it with the rail fitting in the vise and a box-end on the flare fitting. I found a used "Stanley PROTO" 5/8" wrench on eBay with a 6 point end. A friend has Oxy-propane set-up which we can likely use to concentrate the heat on the fitting. I've removed a lot of difficult fasteners but I've never encountered one this difficult.

There was a strange cover over my lower line and so I couldn't see what we were dealing with. Had I realized that lower line cover was just a cover I would have tried to remove the line without disturbing it but I would have never expected it to be so difficult. It makes me wonder how anyone ever changes the regulator because the line assembly is very cleverly 2x the same line just rotated around 180 degrees.

Scott

Jaks79Britz

Just wanted to close this thread out for anyone else curious about the AC Delco fuel injectors. After all the discussion above and research, I ended up moving forward with the install and it all fit into place and getting the 39 psi as needed.

The injectors came with all the two o-rings each, so you don't have to buy them separately like I did.
79 Eldorado Biarritz
79 Coupe Deville

79 Eldorado

#15
Jack,
The Standard Motors injectors also came with the upper o-ring. Initially they looked black but you can see that they are in fact very dark brown. I mention that because it's an indication of the material type. As some may recall I had researched o-ring types for another project and one of the technical material experts recommended flourosilicone material, normally blue, if there is a chance of seeing gasoline and alcohol containing gasoline. I have been using only "pure" gas but I was able to find flourosilicone o-rings and so I used them on top. On the bottom the Fel-Pro kit comes with square cross section seals. Those are just vacuum seals though. I would have still used flourosilicone but to match the geometry of the square seal would require something very likely not "off-the-shelf".

So I'm curious... the AC Delco you mentioned came with both o-rings. Did you mean an o-ring and a square seal or were they both really o-rings? I would be interested in knowing because if the lower really was an o-ring it would make putting a better material kit very possible.

Mine is getting closer... We finally got the flare fitting loose for the supply line. I've done a lot of tough fasteners. This one was the most difficult fitting I've ever had to remove. A friend who was a mechanic for years also said the same. We finally used oxy-propane but even that didn't work until we got it glowing orange, clamped in the vise and then turned the fuel line. That allowed grabbing the two sides more securely. The crazy thing was there was zero corrosion, threads were perfect and there were no signs of any crazy thread locker etc. Seeing it apart neither of us could believe it was so difficult to remove. It was to the point I'm certain almost nobody would believe us. I duplicated the line using Cu-Ni material but I will use -6AN where it connects to the rubber supply line because I don't have a bead tool for 3/8" line.

Scott
PS: My FIV is prototype #1 and my sensors are very early prototypes as well before I found the OE connectors so the ones on the prototypes were 3D printed TPU.
EFI CadillacOlds 01SE2022.JPG

Jaks79Britz

Scott,

The rings that came with the ACDelco injectors were an o-ring on top and the square ring on the bottom.  I didn't realize that the "o" referred to the shape of the ring.   

It's pretty wild you had such a hard time with that flare fitting only to see that threads looked normal.  Glad to hear you finally got it out though. 
79 Eldorado Biarritz
79 Coupe Deville

79 Eldorado

Ok the square profile cross section makes sense according to the kits. I suspect it would be possible to create a seal with o-rings or a combination of an additional metal piece plus an o-ring. I'm not going to worry about that for a while but I have the aluminum manifold if I want to try to create something with a flourosilicone seal sometime.

That fitting was nuts. I really had to search to find a brass version for the inverted flare for 3/8" tubing. I wanted brass because I was convinced, by the effort required, there was a corrosion issue. Now that I know there was not I'm wondering if there were sealing issues and making GM turn to "heavy-handed" torque. The original line was double flared. I used Cu-Ni and I also double flared it. Cu-Ni normally seals better than steel so fingers crossed because I won't use Hulk-hands on it during assembly.

I'm also converting my distributor to non-ESS. I started taking it apart today and only stopped because I couldn't get the roll pin out of the lower gear. I've done that job before on other distributors so I didn't expect an issue. I was able to remove the one in the speed sensor. That was a scary job. The speed sensor is cast aluminum and so I very carefully used my press to push it out. That roll pin was at least easy to set-up in the press. The lower one is not because that area is difficult to support. I'm taking a ton of photos and will hopefully write it up for others.

Scott

bcroe

Looks great so far.  We expect all the pics to turn
into a full blown article on how-to.  Bruce Roe