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'78 Seville injector seal replacement

Started by 78Elegante, April 20, 2020, 02:17:02 PM

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78Elegante

To keep technical talk in the correct forum, I started a new thread over here.
In my introduction post (http://forums.cadillaclasalleclub.org/index.php?topic=159785.0) the discussion was about more than one subject, so I decided to make a separate topic about injector sealing for the 70's fuel injected Cadillacs.

As I live in the Netherlands, I have limited access to US parts. We have some US part suppliers, but they don't stock specialized, or model unique parts so I have to order them from the US.
My main source is RockAuto because they are easy on shipping internationally.
Last week I received 7 boxes of maintenance parts for my Seville and included was a little box of injector seals (Standard SK2) which I tried to install yesterday. Without success.
After installation and switching on the ignition, fuel was squirting out everywhere.
Today I took the injectors out and it was clear that installation wasn't done right.......

So, Bruce already put me in the right direction because I installed the injectors by pushing them in the manifold seals first and after that pushing the fuel line on by tightening the clamps that hold the injectors and fuel line in place.
As you can see on the pictures this did result in a lot of broken seals.

In the second picture you can see the difference between the old and the new seals. The new ones are more ring shaped.

Anyway I need a set of new seals. Back to RockAuto and it seems that they have a supply of Fel-Pro seals for almost nothing (except shipping to the Netherlands).
I bought some sets and the story will continue when they come in.

The top heads I will reuse and to be honnest I don't know where the copper washers are supposed to be installed. I didn't see any of them when taking out the injectors.

To be continued.
Antoon

bcroe

The idea was that the rails might not reseal well put back together,
so you put the copper washers in the rail joints to help.  I have
never needed to use the copper washers. 

I presume your original seals were in scary condition?  Bruce Roe

jagbuxx #12944

#2
Here’s a photo of one of the copper washer example from mine plus a photo from the Cadillac Seville Supplement Serviceman bulletin, Jan 1976 regarding installing the washers during service.
My car was fine except one injector was leaking rather than the seal. I had one injector physically cracked during removal. I sent the other 7 to MotorMan in Michigan to check and replace the small filters in the injectors. 6 were good, 1 was leaking. Our member Bruce sent me 3 replacement injectors and I sent those to MotorMan and they checked ok. So now currently I still have fuel seep at the rear crossover rail plus it seems like running on 7 cylinders. For now I had to walk away.
Good luck on the Seville, it looks gorgeous
Frank Burns #12944
76 Coupe d'Elegance EFI Galloway Green Firemist
70 deVille Convert San Mateo Red
61 Coupe Deville Bristol Blue
41 Series 61 Deluxe Coupe 6127D Black
08 STS 3.6 1SC  Thunder Gray
16 GTI Gray
03 T-Bird Black
16 Grand Cherokee Summit, Granite
19 Tiffin Phaeton 40AH
07 Corvette Blue
20 MB S450 White

"Whatever the occasion, there
is no better way to arrive than in a Cadillac.

78Elegante

The old seals didn't look that bad. They only leaked after we took the car from storage after 2 years, so I think that they sealed again after becoming wetted by the passing fuel.
But anyway, now all injectors are out, I will have to use new seals to put everything together again.

Then, about the copper seals:
When I look at the application information of seal kit SK59 (Standard Motor Products), I noticed that the Seville is only mentioned until '77, so maybe the fuel rail changed in '78 in a way those copper washers are no longer needed.

Phil Weber

Looking in the parts book all models 76-80 had the copper washer . Listed as # 1608786 Gasket Fuel Rail Fitting

http://www.gmpartswiki.com/getpage?pageid=53091

Phil

79 Eldorado

I also bought a kit but I haven't installed it yet. It looks like on the rail side there was a square cross section seal and the replacement is a round o-ring.

When I see the round o-ring broken as it is in Antoon's photo it looks to me as if the o-ring was either too large or the o-ring "rolled" to where it shouldn't be due to possibly the shape or the order of assembly. I suspect the original was a square cross section to help avoid rolling during assembly. If it is the correct size to work maybe some lubrication could help but there are o-rings which can have a drastic reaction to the "wrong" lubricant and knowing what the material is compatible with is not always easy especially if you don't know the o-ring material. I don't have advice but that's my observation having put together quite a few o-ring joints.

Regarding the grommets on the bracket I think I would try assembling two different ways on a single injector with the injector and bracket loose in my hands to see if that part of the assembly alone is easier one way or another. I mean do you install the grommet in the bracket and then push the injector into the assembled grommet or does it go together easier/less effort/less force if the grommet is assembled on the injector first and then the assembly is pushed into the bracket. I've seen similar assemblies where there is a big difference.

I hope things go well with the second try Antoon. I don't like the way those o-rings look so I hope you find somethingg eye opening which drastically changes the situation. Sometimes replacement parts have a slightly different design. Sometimes that's good and sometimes it's not. It looks like all of the available selections on Rock have o-rings.

Scott


79 Eldorado

I just read the posts in the general discussion area. I was thinking of the same thing which Bruce Roe mentioned regarding the timing light. I will add the quote here to tie in the comment:

Quote from: bcroe on April 20, 2020, 11:50:00 AM
Those injector connectors are not great for this age, try wiggling them for a good connection.  I think you can feel them click at
idle, and taking one off ought to cause a change.  What we need is a clamp on meter that shows the injector pulse is actually
flowing, wonder if a clamp on ign timing light on one wire could do that?  Bruce Roe

I should be able to try my timing light with RPM readout with the clamp around an injector wire in the next few days.

Another disturbing thing, it seems somewhat of a consensus, that those upper o-rings as substitute for the square/rectangular seals are not really a good replacement. At minimum it seems like it creates some added risk in assembly as I suspected in my prior post. And after reading Bruce's comment about different o-ring cross section I still suspect something to do with less than ideal size.

The material compatibility charts are pretty available. I just found a very good table. I'm thinking using that table I could either find a better fitting o-ring, in an acceptable material, for that location. I could possibly look into if a square cross section version could be made. It really bothers me when brands which generally have a good name seem to miss something like this.

Bruce also mentioned NAPA and another brand having the same inside bag markings. I've noticed situations like that as well. There was a really professional looking job done on the replacement thermostat housings. The problem is the dimensions for the "goose neck" which gets the small piece of 3/4" heater hose is completely wrong and it won't fit. I would need to dig to find the brands but I found 2 different brands with exactly the same issue. I finally ended up buying a used one from Bruce. I had already detailed/painted the new replacement so I couldn't return it. It's one of the most beautiful replacement pieces I've ever seen...which is completely useless for the intended purpose. Really sad.

Scott

79 Eldorado

#7
I thought I would post some information regarding what I found on material compatibility. This information is from the Minor Rubber Company. They have a really extensive chart which you can move through the list by selecting the first letter of the chemical which you are interested in. Then just look across the top and identify a material which is compatible.
https://www.minorrubber.com/compatibility-chart.html

That sounds simple but you can see that the best "common" (easily available) o-ring material for gasoline is not that great with ethyl alcohol. So in this case we want to find something with good or excellent for both gasoline and ethyl alcohol. The "A" rating in this chart is recommended. Anything less than "A" has at least a minor reaction with the chemical in question. Some of their own specialty products are rated as "A" for both but assuming we are normal people I'm not sure how easy it would be to get products made from specialty materials.Probably searching those names and either "seal" or "o-ring" is probably a next logical step to see what's out there. 

Most of the other soft parts in our system are likely not compatible with ethyl alcohol either unless the companies designing the replacement parts thought to keep that in mind. I would like to think so but I don't like blind faith when it comes to material compatibility.

Can someone post some dimensions of the original square cross section seal used on the top? Understand there will be compression set but that's a starting point.

Scott
Edit: Gallic Acid happened to be the line above gasoline so that's the only reason it's on the chart.... I didn't bother cutting and capturing again to remove it.

79 Eldorado

I just found another compatibility chart and it looks like Viton might be an available and good choice. If someone can post the dimensions of the square seal I will try to find a replacement.

Scott

78Elegante

#9
We can agree that the old and the new seals are not the same.
I'm not convinced yet that the new, ring shaped, seals are worse than the original, more bus shaped, seals.
What I know is that I didn't install them correctly which caused the new seals to break, so I don't know if they would have sealed good when installed correctly.

Then the discussion about the copper washers that are not included in most of the sets of replacement seals.
I took the injectors out without taking out the fuel rail. I only had to disconnect the main fuel line on the back of the motor to be able to lift the fuel rail enough to take out the number 5 and 7 injector. I highly doubt if there is a copper washer in that connection.
Now the question is if I will be able to reinstall the injectors with new seals without taking out the fuel rails. For sure it would be much easier.
I hope I don't need them...... It will be another expensive shipment from the US to here to get them here.....

My new seals are on their way. I ordered 10 sets, so I will have something to play with when they arrive. I will let you know the result.

I also measured the old seals with my cheap Chinese tool (and these are the size after who knows how many years in the engine):
Inside diameter: 0.299 / 7,59mm
Outside diameter: 0.409 / 10,40mm
Height: 0.090 / 2,29mm

I also measured the top of the injector. The place where the seal sits is 0.3075 / 7,81mm
Another important size to know is the inside of the fuel rail where the seal sits. But then you will have to take out the fuel rail.

79 Eldorado

Antoon,
Good points and glad you thought to get multiple sets given part cost vs shipping.

I wanted to follow-up with one thing I didn't initially expect and others should be aware of regarding alternative materials. I found 3 different sources showing operating min/max temps for Viton. It seems it's not recommended for extremely cold temps. All 3 sources listed a similar minimum recommended. Most automotive applications should be listed down to -40 (the one temp where C or F doesn't matter). The sources I saw listed the min at -26C ; -10F (-23.3C) and -15F(-26.1C).  Those are all really cold and below where I would try to even start a car I don't use in the winter but it would still make me hesitate before I decided to use Viton as a substitute. I did find a couple of other materials and I will check based on the sizes you measured but let's see how you do once your parts arrive.

Also since so many kits are on their way an easy compatibility test is to soak the material in the substance for extended time and measure the swell. Also note any color change in the fluid. I would need to verify the exposure time recommended to check but I think it's somewhere around 72hrs to max a couple of weeks so not crazy long and probably checking at 24, 48 and 72hrs plus a longer time, like 1 to 2 weeks, would help tell how aggressive the attack is. My thought being how well was the material in the kit thought out. The exposure would even work on the parts which broke during assembly.

Scott

Phil Weber

Antoon

The seal for the injector to rail is definitely an oring seal . If you look again at the parts page you will see the oring listed .

Might I suggest that the shape of your original seals is the result of the oring being squeezed into the rail socket , between two flat surfaces , and after 40 years it has set to that shape .   

Phil

78Elegante

Phill and Scott,

That means that the measurements that I took in fact are worth nothing and should be discarded.
The current size or shape of the seal doesn't say anything about the original size and shape when they were installed.

Antoon

79 Eldorado

I'm surprised. If that's compression set it seemed to have done an excellent job of creating something which looks like an original shape. That said if Phil found an original reference then my eyes are playing tricks on me.

Let us know how the install goes. Based on your prior experience I would try using something compatible as a lubricant. If those o-rings are the correct size they likely rolled during assembly.

Scott

78Elegante

My new seals came in yesterday and the 10 sets I bought are definitely from different batches.

We have a long weekend coming (Monday is our king's birthday) so I will find time for a second (or third  ;)) try.
As lubricant, I will use Vaseline again, but I will use more on the top and I will mount the top first. And I will come back with the result.

79 Eldorado

The package on the left shows 350 and VINs B, R, 8. i know "R" is normally used for the Oldsmobile 350, "N" for the diesel and I think some years used "L" for the Chevy 350. I don't know the "B" though. And was the "8" just to designate 8cyl or was it in some of the VINs as the designation for the engine type?

Not directly related but since the packaging showed the designations and there are a lot of knowledgeable people here I thought I would ask.

Those arrived pretty fast it seems. Anxious to hear how it goes.

Scott

78Elegante

#16
I can only tell that the 'B' is de Olds 350 in the Seville. See the VIN in my car: https://www.specialtysales.com/vehicles/1978-cadillac-seville-13299
And the '8' is the 350 EFI (Cal only) that was used in 1980 in the Seville (and maybe in other Cadillacs).

bcroe

Quote from: 78EleganteI can only tell that the 'B' is de Olds 350 in the Seville. See the VIN in my car: https://www.specialtysales.com/vehicles/1978-cadillac-seville-13299
And the '8' is the 350 EFI (Cal only) that was used in 1980 in the Seville (and maybe in other Cadillacs).

Also used the same equipment in the California 1980 Eldorado.  Bruce Roe

jagbuxx #12944

#18
Finally got my 500 sorted. Found 2 injector connectors not fully snapped on. Always good to walk away and come back later when something’s not right.
As for seals, I did use the Felpro kit for the injector and manifold seals and used the “Standard” kit SK59 for the copper washers and top hat seals.
When I removed my fuel rails, it did have the washers installed already. Also, when reinstalling the rail assemblies, you should have the injectors already set in the rail, also have the electrical connections oriented in the correct direction for minimal handling once installed...
Frank Burns #12944
76 Coupe d'Elegance EFI Galloway Green Firemist
70 deVille Convert San Mateo Red
61 Coupe Deville Bristol Blue
41 Series 61 Deluxe Coupe 6127D Black
08 STS 3.6 1SC  Thunder Gray
16 GTI Gray
03 T-Bird Black
16 Grand Cherokee Summit, Granite
19 Tiffin Phaeton 40AH
07 Corvette Blue
20 MB S450 White

"Whatever the occasion, there
is no better way to arrive than in a Cadillac.

78Elegante

#19
So, a quick update to finish the sory:

Yesterday I had my second try.
I lubed the O-rings with Vaseline and wiggled and turned them carefully in the fuel rail first before pushing them in the manifold.
After tightening everything I switched the ignition to start the fuel pumps and immediately I heart fuel coming out somewhere.
It was the number 7 injector (the most difficult to reach) that was still leaking........

So, third try. Replaced the O-ring of the number 7 injector again and this time it looked good. So I started the engine and it fired right up!

Here is a little write up for future reference.
To take out the injectors I found it necessary to loosen the fuel rail at the point behind number 7, where the rail coming from number 8 attaches. This 'breaks' the circle of the fuel rail going around the 8 injectors, giving you some flexibility in the fuel rail.
I also loosened the two rear bolts of the throttle body (they hold two brackets that prevent you from lifting the fuel rail) and a clamp on the front side of the engine which holds the vacuum line going to the fuel pressure regulator (this gives you a little space to lift the fuel rail in the front).
Of coarse you need to loosen the four clamps that hold the injectors down.

Installing is the other way around.
When installing the injectors, do the top side first after lubing the O-rings with Vaseline (the clamps will prevent them from falling out) and then push the rail, per side, with four injectors in place.

Bruce Roe advised me to use the Fel-Pro ES 72099 seal kit and I advice to buy at least two sets when planning this job. I took me three attempts to get it done and you don's want install seals for a second time.
In my first attempt I used the Standard SK2 kit. I cannot say if they are good or not because I broke most of the O-rings due to a wrong installation order.
Both the Standard SK2 kit and the Fel-Pro ES 72099 do not include the copper seals for the fuel rail. I only disconnected that fuel rail on one place and it seems that I reconnected it without leaks, without installing a new copper seal.

All in all I think everybody can do this job. It is not difficult and now that I have done it more than once I would estimate that it can be done in two hours.
The tools I used were a 1/2" and a 7/16" socket with different extensions (especially the clamp that holds the vacuum line on the front of the motor is a bit difficult to reach) and a 16mm wrench (I don't have imperial wrenches yet) for the fuel rail.