DIY: 1998 S70 Fuel Injector O-Ring Replacement

[QuirkySwede]

Common source of a fuel smell under the hood is one or more failed fuel injector o-rings. While not a full rebuild, this covers most of the ground for a 1998 Volvo S70 GLT. The ideal time to do this is when you will have the intake manifold off (e.g. PCV system service) so you can remove any pintle caps/washers that might break and fall in (more below).

1. Use a T-25 torx bit to remove the screw then cover over the throttle linkage.
2. Grab the backside and unsnap the injector cover, pivot forward, and remove. There is a catch near each end to focus on should it prove stubborn.
3. Remove each of the fuel injector connections going from left to right. If you have room, press down on the wire hoop which will move the sides out allowing it to slide off.
4. Should it prove too dirty or awkward to do #3, use an awl or small, thin screwdriver to pull one side of the hoop off to the side, then use needle-nose pliers to rotate it off and to keep it from falling down into the engine bay, remove connector, then reattach hoop. Now is convenient time to replace the protective loom covering the injector wiring that is often brittle and cracking away with similar, but do not simply spiral wrap it with electrical tape -- poor barrier and PITA to deal with at any later service.

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5. Remove the blue cap at the right end of the fuel rail and depress the Schraeder valve pin to relieve and pressure in the rail. Though hard to see, a cap from a carb cleaner can about 1" in diameter is used to catch the fuel. Replace blue cap securely.
6. Using a 14mm wrench on the lower part to prevent it from twisting, loosen the fuel connection with a 17mm wrench.
7. Pinch the barbs in on the white tab in the middle of the fuel rail, push it down, and rotate away from the hole on the fuel line below. Then use a 10mm socket to remove the bolts on either side.
8. Grab the fuel rail firmly and pull it out. The injectors are held into the rail with a clip. Each injector will likely be somewhat stuck and thus a little wiggling will be needed, but take care to pull out the rail and injectors as squarely as possible to avoid damaging any components. As soon as it is free, place your finger over the fuel inlet, remove rail from car, and drain gas remaining in the rail out the inlet into a suitable container. (Good time to plug injector holes with some towel paper, clean seats, blow out with compressed air, then remove paper for a final wipe down.)

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9. Place rail upside-down, remove the three torx screws, then slide back and remove the long retaining clip for the injectors and fuel pressure regulator.
10. Setting them aside in order, remove one injector at a time. Note brownish-yellow varnish from gasoline in fuel rail.
11. Top o-ring should easily pull off. Use a new razor blade to cut a slit and remove lower one to avoid damaging the light brown pintle cap (common name, though since this type is not really a cap it is sometimes called an o-ring retainer or pintle washer). Clean body with carb, not brake, cleaner and check for cracks or other damage. If any dirt or corrosion remains on the o-ring seats, use some 0000 steel wool to polish it off (do not use sandpaper) then re-wipe with paper towel saturated with some carb cleaner. Lube the o-rings and contact points prior to install. Top will slide on. For bottom o-ring, turn injector upside-down and place on a sturdy surface, place white cone on top of pintle washer, and quickly slide lubed o-ring down cone and over ring. This method best avoids tearing, nicking, cutting, or other damage to the o-ring. I used di-electric (silicone, non-conductive) grease, which is also good to smear on the injectors' electrical contacts.
12. Upper o-rings looked to be in good condition, but at least one was leaking as that's the only side under fuel pressure -- replace them all. Lower ones (pictured) all showed signs of age and heat. Lower one bake from the heat off the intake manifold while upper ones are cooled via fuel flow, distance from engine, and heat sink effect of fuel rail and cover.

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13. While in there, I removed the fuel pressure regulator as well. Note hole cleaned with carb cleaner sprayed on paper towel on right and FPR and injector hole on left with gasoline varnish. Clean all holes and contact surfaces as done for injectors (carb cleaner on paper towel, 0000 wool if needed but wiped afterward) and smear a thin amount of grease on any o-ring bore which will facilitate both assembly and let the o-ring "float" enough to seal at various operating temperatures.
14. Note FPR o-ring is not the same size as an injector o-ring. They have the same OD (and same bore in fuel rail), but the FPR one is thinner. Pictured L-R are a new injector o-ring, FPR o-ring (lubed and reused), old injector o-ring noticeably compressed over the years. Installation is removal order in reverse.

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RESULTS
Fuel smell under hood gone for under $5 and car runs fine.

OMG! I'VE LOST A PINTLE WASHER SOMEWHERE!
Removing the fuel rail injector assembly from the intake manifold will often require some twisting to free the baked-in o-rings. Finding old, broken pintle washers is not uncommon. But are they still in the manifold? Will they get sucked in and destroy my engine? First it's best to inspect and remove any broken pieces, hence this service being ideal for when the intake manifold is off where you can hold the butterfly open at the MAF end and blow it clean, blow into any chambers where the intake is closed (shine light down spark plug hole and look into intake port), or blow compressed air into the spark plug hole out the intake valve, but that will require rotating the crank by hand after you blow air through the cylinder whose intake is already open first, then follow the firing order as each intake comes open for any cylinder with missing pintle pieces. Then again, there's a good chance those little plastic pieces were that way long before you started the service and have long since been broken up, sucked through, and or burned up by the metal components and combustion temperatures. Your call.

PARTS
Recommended:
Advance/OReilly: BWD - Fuel Injector Seal Kit, Part # : 274573, limited lifetime warranty
NAPA: CRB 212079, w/ 36mo/36k mi warranty
~$4.50, TWELVE o-rings, $0.38ea, and a cone to get rings over retainer

Alternative:
Volvo: 30731375, 16245
Advance/OReilly: BWD - Fuel Injector Seal Kit, Part # : 274571, 1-year warranty
NAPA: CRB 212093, w/ 36mo/36k mi warranty
~$1.60, just two o-rings, $0.80ea,

Not recommended:
Advance/OReilly: BWD - Fuel Injector Seal Kit, Part # : 274081, 1-year warranty
NAPA: CRB 212085, w/ 36mo/36k mi warranty, or MPF 312085 w/ 12mo/12k mi warranty)
~$4.00, two o-rings, but doesn't use spacer and pintle cap/retainer is wrong shape (cup, not washer),

Incidentally, ran across these which look similar if you need something right away and don't have a local dealer, but you have have to compare them yourself (take a used one in)
Volvo: 3528216, 77760, see NAPA # ATM 3528216 (fuel rail to injector)
Volvo: 3528217, 77762, see NAPA # ATM 3528217 (injector to manifold)
http://volvospeed.com/vs_forum/topic/78 ... t-is-what/


KITS
If you want to service more than just the injector o-rings, consider one of the following kits, especially if you want to replace the pintle caps/washers (aka o-ring retainers) and or basket screens in top of injector. Screens can be removed by clamping an appropriately-sized wood screw in a vise, point up, screwing injector on to engage, then pulling up.
Pintle Cap/Washer / O-Ring Retainer: 13.2mm OD (0.52") x 7.6mm ID (0.30") x 1.96mm Thick (0.077") Replacement: cut a slit in the old one with a sharp knife or razor then twist off with pliers. Some make be so old or brittle that they crack apart and can be removed by hand. Heat new one with boiling water or hot air to about 200 F and press injector firmly down onto washer, best supported by a metal washer or hole underneath that allows the nozzle to pass through.
(in no particular order)
http://www.ebay.com/itm/Bosch-Type-3-Fu ... 0878614136
http://www.ebay.com/itm/Fuel-Injector-S ... 0862944640
http://www.mrinjectorparts.com/store/p1 ... m_TF4.html
http://www.mrinjectorparts.com/store/p4 ... _TF7_.html (tosses in an extra of each piece, so a 4-cyl kit will do a S70, or the 10-cyl kit will do two S70s with an "oops" spare)
http://www.bonanza.com/listings/Bosch-T ... d=11505041
http://tradergreg.ecrater.com/p/1099170 ... injector-o
http://injector-rehab.com/shop/Bosch-Ty ... -Flat.html
Couple places in China listing the pintle washers as 13.3x7.7x2mm PET/Nylon for comparison
http://www.gasgoo.com/auto-products/mat ... 11607.html
http://www.aliexpress.com/store/product ... 75230.html

OTHER DIY INJECTOR SERVICING LINKS
No need to re-write what they have. Different perspectives.
http://www.rowand.net/Shop/Tech/DIYFuel ... eaning.htm
http://www.e30tech.com/forum/showthread.php?t=85631
http://forums.bimmerforums.com/forum/sh ... -injectors

PROFESSIONAL REBUILD
There are plenty of places that offer to rebuild your injectors or sell rebuilt ones that are cleaned, stripped of the parts in the kits above, cleaned, tested, and then have new o-rings, pintle caps/washers, screen baskets, and spacers as needed installed.

INJECTORS PICTURED
Bosch Type 3 (aka Type III) fuel injector with "flat" pintle cap or o-ring retainer
Bosch: 0 280155759, 0280155759, 0-280-155-759, 9454556
Flow (@ Rated Pressure): 30.0 lbs/hr, 315.3 cc/min, 226.8 g/min
Rated Pressure: 43.5 PSI, 3 bar
EV1 feed, high impedance

FUEL PRESSURE REGULATOR AND O-RING
Volvo: 1275658 (comes with o-ring)
FPR o-ring not listed separately, and might not be available via Volvo.
Volvo "Fuel Pressure Regulator O-Ring" 30713581 and 98925 have not been measured for comparison, but likely different as it appears they for a different FPR.
FPR O-ring measured 14.3mm OD x 9.5mm ID x 2.4mm thick.
If in need of replacement, consider
2.4mm x 9.6mm Viton 75 Metric O-ring or 2.5mm X 9.5mm V75 Viton O-ring Black
Make sure it is Viton, which is suited for fuel use and temperature range unlike other "rubbers."
More about Viton:
http://www.fbs-online.com/Centre/Prod/V ... om-res.htm
http://www.allorings.com/compatibility.htm

[jreed]

Gorgeous write-up! Thanks. I really appreciate the list of parts, sources and links to additional information... Really nice! Thank you!

[biclops]

Thank you Thank you Thank you!!!!

That pintle cap information saved me a huge headache! I have been sweating for a day and a half now trying to find a replacement for the washer style pintle cap on my '98 v70 GLT injectors! One broke off when I was removing the fuel rail from my intake manifold for a head gasket job. My local volvo dealer, the only one for 80 miles, told me I would have to buy a new injector! Ha! I am glad they were wrong. I just ordered the pintle washers themselves, as I already have the o-rings and am not planning to remove the injectors from the fuel rail.

Thanks again!!!!!!!!!!!!!!!!!!!!!!

[j-dawg]

taking out the fuel rail and injectors on my 99 T5, i cracked the pintle washer on injector #4 (see attached). do the parts in the links in this post work for the blue T5 injectors? has anyone got a more reliable source? i'm moving at the end of the month so the car needs to be operational by then, and i am wary of ebay sellers and shipping speed.

[erikv11]

One of the great things about eBay is that most sellers have superfast response time for shipping. It's part of the culture and has overwhelmingly been my experience. Check the seller reviews, if there are no complaints about shipping time then and they are in the US then don't worry at all about that part. I'd drop the $10 and order one up. Or spend $20 on a used blue injector (again, check eBay or post up a wanted ad here) just to make sure you can drive the car when you want to.

To your main question: I don't have experience with the injector parts for blues so can't say for sure, hopefully someone who does will chime in.

[j-dawg]

i've read that the injectors are all the plastic-body Bosch Type 3 units, and the washer-style pintle cap should work for mine as well.

i'll buy a kit, give it a go, and report how it works out. you're probably right about the ebay sellers - i ordered a book with free shipping on july 2, and it arrived on the monday after the 4th weekend.

[j-dawg]

update: haven't driven it yet, but i bought and installed o-rings, filters, and pintle caps from ebay seller "silvershot_platinum" and had them in, like, three days installation seemed daunting, especially the filters and pintle caps, but it turned out to be easy peasy. (this is for my 99 T5, blue injectors.)

here's what my filters looked like:

guess which one's the old one

the torn and deformed bits are because i pulled 'em out with a wood screw. this took a lot more muscle than i expected, but the surfaces inside were clean and undamaged. i don't know if the brown discoloration of the filter is a bad thing or normal, and the bore of the injector looked clean and perfectly smooth, but it certainly couldn't hurt to replace the filter. the links suggest to tap the filter in with a hammer. i found it was easier to press it in against a hard surface to get it started so it wouldn't bounce out when i tapped it. be careful to keep everything clean here.

pintle caps were easy to replace. i cut the old ones off with a razor, being careful not to nick the o-ring seating surface on the injector. i soaked them in boiled water for a minute or so to soften them up. the hole in the handle on a crescent wrench was the perfect size to let me push the injector into the pintle cap and it gives a nice satisfying snap when it's in. on the cardboard below are some old o-rings and pintle caps, and the new hotness is in the fuel rail. use a tiny dab of a thin oil to lubricate the o-rings. the injectors don't go into the fuel rail and manifold easily, and you can damage them if you force it.

prepare your work surface for spilling gasoline everywhere

while i was in here, i took the opportunity to loom up wires whose factory corrugated plastic loom had totally disintegrated. i used Techflex F6 1/4" ID split braided nylon loom, secured with zip ties. easy stuff to work with and looks good, though it would look better if i wrapped the ends in electrical tape. the melting point is around 450F, so i'm not worried about its suitability for the engine bay. 10ft of this stuff goes a surprisingly long way. i think i'll buy some more and loom up more wires just because it looks good - you can't actually see these wires with the fuel rail and spark plug covers in place.

imma buy more and loom stuff up just because it's fun

[d_g_bates]

just wanted to say 'thanks' to QuirkySwede... i had cylinder #5 misfiring like mad started last night
and kept going today.

read this write-up, and photo #2 showed me how to access the injector connectors.... #5 was loose with
intermittent connection.

plugged in all the way, cleared the codes and all is better now.

again, thanks for the awesome write-up.


~dave in Canada

[MadeInJapan]

I read your thread with interest. I had to do this in a pinch on my '98 S70 a few years ago. I found that the box of different o-rings for injectors from Autozone has 1 (yes, just one) in it that is the correct size. I used it and have not had any issue since. Mine reeked of gas after a head job by someone else. The smell never went away until I pulled the injectors and found one bad one, and when I grabbed it, it fell apart. I had none on hand and it was the weekend! I usually don't buy parts for my cars at Autozone but this time, they were the go-to and they came through.

[scot850]

I have bought O-ring kits from this company several times and they have been helpful and price is excellent relative to Volvo. Liked the kit as it comes with the injector filters, O-rings and replacement pintle caps (the plastic bit on the end of the injector). It also comes with a screw the correct size to help extract the old filters.

Their response was good when I had questions. Dimar motorsports LLC

http://www.ebay.ca/itm/Fuel-Injector-Se ... 416efd3bb9

Not had any issues with the supplied parts.

Only thing to watch is make sure you get the correct length of injector filter. There are 2 lengths and if I recall correctly, the shorties fit into injectors that use long and short, but long filters do not work in those with short filters.

Also consider replacing the rubber spacer washer on the top of the injector (if it has them) and the lower spacer ring (again if it has them). I bought them from FCP Euro. I recall they had OE and aftermarket.

Neil.