1984 GL 1.8 Oil Pump rebuild service

[grasscutter96]

I don't often post here, but couldn't find a detailed thread on this, so decided to post one of the biggest culprits on an engine that drips.

 

Hate leaky engines, and have been systematically working through all the 'culprits'.

 

Its usually the oil pump, but decided to cover all the other bases first.

1- Oil Pressure sender. (removed, resealed threads, and re-installed)

2- Leaky pan gasket. (definitely was a crusty gasket, but didn't fix the oil dripping).

3- Rebuild oil pump. (Yup. Underside of engine is clean again!)

 

Taking your time, its about an hr. job @ the longest.

Keep everything spotless clean.

 

Don't need to drain the oil, as the pan is below the pump.

1-Remove the 4 10mm bolts.

2-Remove wire to oil sender.

3-Lightly tap on the oil filter. (TAP it. Don't pound it!)

4-Do NOT insert any screwdrivers, or other prying tools, to pry the pump out.

(you will damage the gasket surface, and cause a bigger leak).

5-Light tapping and wiggling and the pump will come right out.

 

6-Make yourself a clean work area, and start dis-assembling.

 

Dis-assembly:

1-Remove 2 phillips screws. (Use correct tip. Best to use an impact.)

2-Separate the 2 halves. Slowly! There is a check ball and spring in there!

(note: pay attention to which way the spring goes)

3-Open up your Subaru oil pump service kit, and start replacing all the O-Rings.

4-Use grease on all O-Rings. This will help them stay in place, and help them not get caught up, when installing the pump.

(light grease. You're not packing wheel bearings!)

5-Re-install top half of pump. Watch that spring stays correctly centered.

6-Tighten 2 phillips screws. (Use correct tip, so screwdriver doesn't slip.)

7-slight smear of grease on gasket surface, and install paper gasket.

8-Wipe down any and all areas around oil pump hole (GO SLOW! One bit of gravel in that hole, and you've got major engine issues!!!)

9-Install pump. Again...don't force it.

10-Once its started in the case, put all 4 10mm bolts in the proper place. (depending on which model Subaru, you will likely have 1 or more bolts of different lengths).

11-Using the 4 mounting bolts, tighten them all down evenly (use a 'cross' or 'star' pattern), and slowly 'draw' the pump in.

12-Dont' over-tighten. They are only 10mm.

13-Check oil. Start engine. Enjoy the fact that your engine will drip no more!

 

Options:

A-Spin on a new filter.

B-Might need to remove fan belt for easier access to one of the top 10mm bolts.

 

Pics: 8 total.

1-Pump removed.

 

2-Note o-ring! Not supposed to be 'wavy'! (likely this is the source of my leak).

 

3-screws and 2 halves separated.

 

4- Close-up of # 3. Note spring orientation.

 

5-Removing large o-ring. Use a sharp razor. (NO PRYING WITH SCREWDRIVERS!!!!)

 

6-Old o-rings and new Subaru oil pump kit.

 

7-Greasing o-rings, so they don't fall out when re-installing pump.

 

8-Done. Ready for paper gasket and installed back in engine.

[Señor Brat]

Awesome post! Thanks for the detailed photos. I'll be doing this in the near future as well.

[mikaleda]

Good write up. I just thought i would say that when I do it I throw away the paper gasket and just use gasoline kerosene resistant rtv silicone that will keep it from developing the drip again

Edited December 16, 2012 by mikaleda
Misspelled word

[ajp]

Wow! I second the awesome post. step by step, easy to follow.

 

I have the 84 1800 non-turbo engine and it had the drip going. After narrowing it down to the pump (the drip was most noticeable on the bottom of that sensor unit hanging off the pump, tightened that screw/bolt and it helped a little, but not all the way), I decided it was time to replace the pump. Ordered the new pump, got myself all ready.

 

When I went to take out the pump bolts, noticed one of them was really loose, like finger tight. I proceeded, but the pump seemed to be welded to the block. I beat on it pretty hard, from all directions, but the damn thing wasn't going anywhere. So, not being a mechanic proper, I decided to let someone with experience try it out, thought there might be a little trick to it that I dont know. So I put the bolts back in, tightened them good and snug. And the leak stopped. lucky day for me. no leak since then and that was over 10,000miles ago.

[81EA81]

Looking good! I wish I could say it only took about an hour. It felt like it took me a good five hours just to get the old gasket off,However I did improvise a brass nut as a gasket scraper,It was nice and soft but it sucked to hold on to.Im curious, what did you use?

 

I bought my seals separately,I wasnt aware of a kit. if anybody wants individual numbers here they are.

 

EA81 Oil Pump O-ring part numbers:

 

806915050

 

806949030

 

806914020

 

806938020

 

Body Gasket:

 

424207000

 

Good tip with the razor blade on the large inner o-ring. I had a hard time figuring out a way to lift it up and it was hard as a rock. Razor blade did the trick.

Personally I used clean engine oil on the o-rings. either way seems fine.

 

 

 

 

 

[pressingonward]

I would be cautious about the type of grease you use on the O-rings. Some greases don't play nice with rubber O-rings.

 

Napa sells a 100% silicone grease called "Sil-Glyde" which is safe for any type of rubber. I recommend it for lubricating O-rings, it works really well.

 

I resealed my oil pump recently and it was pretty quick and easy. My only issue was that I didn't realize there were the two screws holding the pump halves together. They were hidden under the paper gasket. Once I found them and removed them everything went smoothly.

 

I use Permatex "Copper Spray-A-Gasket" spray sealant on paper gaskets to ensure they seal well. RTV silicone is not really a good choice for sealing paper gaskets.

[mikaleda]

I would be cautious about the type of grease you use on the O-rings. Some greases don't play nice with rubber O-rings.

 

Napa sells a 100% silicone grease called "Sil-Glyde" which is safe for any type of rubber. I recommend it for lubricating O-rings, it works really well.

 

I resealed my oil pump recently and it was pretty quick and easy. My only issue was that I didn't realize there were the two screws holding the pump halves together. They were hidden under the paper gasket. Once I found them and removed them everything went smoothly.

 

I use Permatex "Copper Spray-A-Gasket" spray sealant on paper gaskets to ensure they seal well. RTV silicone is not really a good choice for sealing paper gaskets.

Rtv copper is some of the best stuff on the market I use it on a lot of stuff. Actually I have used rtv with paper gaskets never had a problem. Also if you use rtv copper you don't need the paper gasket

[pressingonward]

Rtv copper is some of the best stuff on the market I use it on a lot of stuff. Actually I have used rtv with paper gaskets never had a problem. Also if you use rtv copper you don't need the paper gasket

 

I've never liked the Ultra-Copper RTV sealant. It is designed for high temps, but it does not handle high enough temps to be useful for things like exhaust gaskets. All the other Permatex RTV's can handle the temps associated with an engine and are better suited to their individual applications.

 

Every car I've seen come into our shop with ultra copper used to seal an oil pan, valve cover, or timing cover has leaked like a sieve. I'm sure it would work ok if they had prepped the surface properly, but there are better options.

 

In the case of the oil pump, it would be acceptable to use Ultra-Grey, which is designed for high clamping loads (pretty much any rigid aluminum parts bolted together fall under this category, including transmission cases), as a replacement for the paper gasket (as you said). My only concern would be that the slight tolerance change due to the thinner rtv seal would have an effect on the oil pump's functionality. Probably not a problem since the paper gasket is very thin.

 

Non-rigid connections (sheet metal parts such as the oil pan or valve covers) do better with Ultra-Black, which has superior oil resistance, but that's somewhat off topic

[mikaleda]

I've never liked the Ultra-Copper RTV sealant. It is designed for high temps, but it does not handle high enough temps to be useful for things like exhaust gaskets. All the other Permatex RTV's can handle the temps associated with an engine and are better suited to their individual applications.

 

Every car I've seen come into our shop with ultra copper used to seal an oil pan, valve cover, or timing cover has leaked like a sieve. I'm sure it would work ok if they had prepped the surface properly, but there are better options.

 

In the case of the oil pump, it would be acceptable to use Ultra-Grey, which is designed for high clamping loads (pretty much any rigid aluminum parts bolted together fall under this category, including transmission cases), as a replacement for the paper gasket (as you said). My only concern would be that the slight tolerance change due to the thinner rtv seal would have an effect on the oil pump's functionality. Probably not a problem since the paper gasket is very thin. And yes each rtv is made to da Certain thing as I mentioned in my first post use gasoline/kerosene resistant rtv.

 

Non-rigid connections (sheet metal parts such as the oil pan or valve covers) do better with Ultra-Black, which has superior oil resistance, but that's somewhat off topic

Of course you can't use rtv on exaust gaskets duh

I have sealed several oil pumps with ultra copper no incidents it is actually what my parts store listed for the oil pump gasket.

New gen cars are made to use rtv on the oil pan but old gen arn't you have to use a cork or rubber gasket.

And I am talking about oil pump not the thin metal valve covers or oil pans, and as we are talking about subarus I have never seen a Subaru with a timing chain.

Edited December 18, 2012 by mikaleda

[pressingonward]

Of course you can't use rtv on exaust gaskets duh

I have sealed several oil pumps with ultra copper no incidents it is actually what my parts store listed for the oil pump gasket.

New gen cars are made to use rtv on the oil pan but old gen arn't you have to use a cork or rubber gasket.

And I am talking about oil pump not the thin metal valve covers or oil pans, and as we are talking about subarus I have never seen a Subaru with a timing chain.

 

In my experience parts store's computers always default to RTV silicone if they don't have the proper gasket.

 

RTV makes an excellent replacement for the stock cork gaskets on EA81s. Just redid my oil pan using Ultra-Black. No more leaky.

 

I think the diesel Subaru motor has a timing chain, but you are right, that's not really topical to Subarus. I worked in several independent shops so I've worked on pretty much every make and model out there.

 

My point about the ultra copper and exhaust gaskets was that it can't handle exhaust temps, and for everything else on the engine the other types of RTV can handle the temps no problem.

 

Anyways, I'm sorry if I've derailed this thread. I'll restrict any further comments to oil pump resealing.

[mikaleda]

In my experience parts store's computers always default to RTV silicone if they don't have the proper gasket.

 

RTV makes an excellent replacement for the stock cork gaskets on EA81s. Just redid my oil pan using Ultra-Black. No more leaky.

 

I think the diesel Subaru motor has a timing chain, but you are right, that's not really topical to Subarus. I worked in several independent shops so I've worked on pretty much every make and model out there.

 

My point about the ultra copper and exhaust gaskets was that it can't handle exhaust temps, and for everything else on the engine the other types of RTV can handle the temps no problem.

 

Anyways, I'm sorry if I've derailed this thread. I'll restrict any further comments to oil pump resealing.

Agreed :-p

[GeneralDisorder]

Copper RTV will help to seal exhaust gaskets or flanges that have imperfections in the surfaces. It is used quite often for that and works quite well. Exhaust temps drop off dramatically once you are away from the heads a foot or two. Downstream of the header gaskets it's not hot enough to damage the copper RTV.

 

GD

[ivans imports]

ulltra copper subaru exhausts best freind and 10.125 hili coils

[mikaleda]

Cool I learned something new

[grasscutter96]

81EA81: Nice job on the oil pump service. Some times cleaning off gasket material can consume a chunk of time! Nice call on using brass to scrape it.

 

And yes, I called Subaru and asked for on oil pump gasket rebuild kit. I included that picture in the original post. (Mine was for a 1984 1.8)

 

 

Reading through some of the comments I need to address the gasket debate. (Which is kind of like asking 'what kind of oil should I use')

 

If Subaru wanted RTV or any other type of sealer, they would have used it there instead of a paper gasket. (Yes, some other manufacturers use RTV sealants instead of gaskets. But the vehicle in question, does not. And yes, some parts counters show RTV, because they don't care enough to find a supplier for the correct part.)

 

 

To use any liquid gasket INSTEAD of the paper gasket is foolish.

 

Now, before anyone starts getting all uptight... just chill for second.

 

There are times to use a very very very light smear of RTV (or whatever brand you think came down from God above), in addition to the paper gasket. Yes. That's right. SOMETIMES! Why? Because over the course of ownership, your vehicle may have been owned by a gorilla who used a a dull screwdriver to hack away @ the old gasket.

 

Now the sealing surface has scratches and gouges. This is where a paper gasket alone will not do the trick, and a dab of RTV type sealant will help fill in the irregularities.

 

But...don't get confused. Its not the gasket that failed, its the surface. Sure, you can disassemble the entire engine and get it milled. Fail, since its pretty impractical to do that. Sure you can try to sand the surface smooth. Fail again, since its not real smart to introduce sanding grit to an open oil pump hole!

 

But, obviously you want no oil leaks, or you wouldn't have taken a sunny Saturday afternoon to pull the oil pump out.

 

So, yes, be smart with your RTV use. Don't layer it on. If you see it squish out the sides, you can bet it squished out on the inside as well.

 

Use it only IF needed. And don't try to think you know more than the engineers that put the Subaru together. Unless of course you 'are' an engineer... then I apologize!

 

Someone also cautioned using grease on o-rings. The chance of having such a grease in your workshop is highly highly unlikely. Without geeking out and giving a lecture on oils & greases (over 15 years in the industry), just remember they come from the same source. One is liquid, the other semi-solid. A small smear on o-rings during assembly is fine.

 

On the other hand, NOT using anything to keep the o-rings from falling out as you try and put the pump back in.... well... Let's just say.. "Good luck with that"!

[Gloyale]

 

Napa sells a 100% silicone grease called "Sil-Glyde" which is safe for any type of rubber. I recommend it for lubricating O-rings, it works really well.

 

 

Sil-Glyde FTW:banana:

[Dee2]

Excellent post.

 

Thanks for making the effort to document and share. I will be trying this myself as I hate the constant oil on the bottom of the engine and I have always suspected it was from the oil pump or oil cooler.

[Indrid cold]

Nice write up grasscutter96.

[GeneralDisorder]

For rubber o-rings, etc the best stuff by far is Dow Corning 111. It's got a lot of uses in a shop - it also doubles as the BEST dielectric grease you can easily get.

 

As for RTV and the oil pump gasket. Generally not advisable. Anaerobic is a better choice and should still be used sparingly and only to fill imperfections in the mating surfaces as noted.

 

GD

Edited December 23, 2012 by GeneralDisorder

[TomRhere]

I use the D-C 111 here.

Great for lubing o-rings like the one on the EA82 waterpump inlet pipe.

A little of it applied to hose connections, IE; heater hoses, helps greatly on install and later removale

[Ofeargall]

 

I bought my seals separately,I wasnt aware of a kit. if anybody wants individual numbers here they are.

 

EA81 Oil Pump O-ring part numbers:

 

806915050

 

806949030

 

806914020

 

806938020

 

Body Gasket:

 

424207000

 

Thanks for including these! My local dealer couldn't locate the part number for the kit in the first set of images posted.

[81EA81]

Good to hear. Im Glad I could help save some time.

Edited December 30, 2012 by 81EA81

[Dinky26]

Rockauto has a kit, or at least for the 86' Brat they do.

 

 

Looking good! I wish I could say it only took about an hour. It felt like it took me a good five hours just to get the old gasket off,However I did improvise a brass nut as a gasket scraper,It was nice and soft but it sucked to hold on to.Im curious, what did you use?

 

I bought my seals separately,I wasnt aware of a kit. if anybody wants individual numbers here they are.

 

EA81 Oil Pump O-ring part numbers:

 

806915050

 

806949030

 

806914020

 

806938020

 

Body Gasket:

 

424207000

 

Good tip with the razor blade on the large inner o-ring. I had a hard time figuring out a way to lift it up and it was hard as a rock. Razor blade did the trick.

Personally I used clean engine oil on the o-rings. either way seems fine.