Rebuilding S4 Mechanical Omp, anyone know how ?
02-01-07, 04:49 PM
#1
Rebuilding S4 Mechanical Omp, anyone know how ?
I may have a leaky omp, im not sure yet but I will soon check, car has about 150,000 miles on it so I wouldnt be suprised if its leaking.
If it is leaking then I need to rebuild it and was wondering if anyone knows where a good guide is or can just help me out.
I found this thread when searching, it has good pics of all the parts on the omp.
https://www.rx7club.com/showthread.p...ht=omp+rebuild
If it is leaking then I need to rebuild it and was wondering if anyone knows where a good guide is or can just help me out.
I found this thread when searching, it has good pics of all the parts on the omp.
https://www.rx7club.com/showthread.p...ht=omp+rebuild
02-01-07, 05:24 PM
#3
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Originally Posted by 87 t-66
And a very good thread that one is.
It's usually the o'ring on the lever that leaks. Usually. McMaster Carr delivers quickly if you order the o'rings.
02-01-07, 10:51 PM
#4
So is this pretty easy to do then ? Ive never taken apart the omp.
Im guessing it should take an hour or so max to actually take it apart rebuild it and put it all back together.
I'm going to clean off the spot where the oil leaks onto and verify to see if the omp is leaking. I'll try to take pics and post.
I think maybe it would be easier to get another extra to rebuild while i keep mine on my car in the meantime...
I see you need 3 different sized o-rings but only 1 person listed a sight where one can be purchased...but it comes in packs of 50. I dont think I need 50 Orings if only 1 in that size is getting replaced.
Anyone who did rebuild their omp, where did you purchase your orings ?
Also read that for the endplates one guy used rtv because he couldnt find the orings (on that writeup post).
Im guessing it should take an hour or so max to actually take it apart rebuild it and put it all back together.
I'm going to clean off the spot where the oil leaks onto and verify to see if the omp is leaking. I'll try to take pics and post.
I think maybe it would be easier to get another extra to rebuild while i keep mine on my car in the meantime...
I see you need 3 different sized o-rings but only 1 person listed a sight where one can be purchased...but it comes in packs of 50. I dont think I need 50 Orings if only 1 in that size is getting replaced.
Anyone who did rebuild their omp, where did you purchase your orings ?
Also read that for the endplates one guy used rtv because he couldnt find the orings (on that writeup post).
Last edited by wthdidusay82; 02-01-07 at 11:03 PM.
02-02-07, 12:13 AM
#5
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On the ends I left the old o'ring in place after cleaning and applied a very small film of RTV around it. You don't want squeeze out entering the oil passage areas. On the end with no o'ring I just applied a FILM of RTV for the same reasons mentioned above.
Fifty o'rings. Now you have spares. They're cheap.
I remove the afm and airpump for easier access. Four 12mm bolts for the airpump and a clamp and three attach bolts for the afm/airfilter. Not required but takes only minutes.
Takes a little more time than you might think removing the omp the first time. Two 10mm bolts but finding the right/best tools to remove them takes a little time. Removing the four banjo bolts from the pump is quick and easy.
Then removing the rod from the omp takes a litte finessing and remember to install the rod with some clearance b/t the lever on the omp and the washers on the rod end. I threaded my rod with a die and put a nut on it for easier clearance changing. It's in the FSM....the clearance reqirement.
The end plates should not leak with the dab of RTV because there is NO oil pressure inside the pump to speak of. Done
Fifty o'rings. Now you have spares. They're cheap.
I remove the afm and airpump for easier access. Four 12mm bolts for the airpump and a clamp and three attach bolts for the afm/airfilter. Not required but takes only minutes.
Takes a little more time than you might think removing the omp the first time. Two 10mm bolts but finding the right/best tools to remove them takes a little time. Removing the four banjo bolts from the pump is quick and easy.
Then removing the rod from the omp takes a litte finessing and remember to install the rod with some clearance b/t the lever on the omp and the washers on the rod end. I threaded my rod with a die and put a nut on it for easier clearance changing. It's in the FSM....the clearance reqirement.
The end plates should not leak with the dab of RTV because there is NO oil pressure inside the pump to speak of. Done
02-02-07, 12:56 AM
#6
Originally Posted by HAILERS
On the ends I left the old o'ring in place after cleaning and applied a very small film of RTV around it. You don't want squeeze out entering the oil passage areas. On the end with no o'ring I just applied a FILM of RTV for the same reasons mentioned above.
Fifty o'rings. Now you have spares. They're cheap.
I remove the afm and airpump for easier access. Four 12mm bolts for the airpump and a clamp and three attach bolts for the afm/airfilter. Not required but takes only minutes.
Takes a little more time than you might think removing the omp the first time. Two 10mm bolts but finding the right/best tools to remove them takes a little time. Removing the four banjo bolts from the pump is quick and easy.
Then removing the rod from the omp takes a litte finessing and remember to install the rod with some clearance b/t the lever on the omp and the washers on the rod end
. I threaded my rod with a die and put a nut on it for easier clearance changing. It's in the FSM....the clearance reqirement.
The end plates should not leak with the dab of RTV because there is NO oil pressure inside the pump to speak of. Done
Fifty o'rings. Now you have spares. They're cheap.
I remove the afm and airpump for easier access. Four 12mm bolts for the airpump and a clamp and three attach bolts for the afm/airfilter. Not required but takes only minutes.
Takes a little more time than you might think removing the omp the first time. Two 10mm bolts but finding the right/best tools to remove them takes a little time. Removing the four banjo bolts from the pump is quick and easy.
Then removing the rod from the omp takes a litte finessing and remember to install the rod with some clearance b/t the lever on the omp and the washers on the rod end
. I threaded my rod with a die and put a nut on it for easier clearance changing. It's in the FSM....the clearance reqirement.
The end plates should not leak with the dab of RTV because there is NO oil pressure inside the pump to speak of. Done
So why didnt you replace all the orings and use rtv instead over 2 of them ?
Explain what you mean by this ? . I threaded my rod with a die and put a nut on it for easier clearance changing. It's in the FSM....the clearance reqirement.
I dont know what a die is or understand what you mean by putting a nut on it for clearance.
Im thinking of probably acquiring one of these cheap and just rebuilding it, because it may take me longer than expected to make sure its done 100% right.
Anyone have one for cheap ?? s4 mechanical omp
edit - also , should I again replace the oring that goes between the block and the omp (oring on the omp mating with block). I replaced this about 2000 miles ago because it was bad but i didnt know if its something you should always replace when you take it apart.
Last edited by wthdidusay82; 02-02-07 at 01:01 AM.
02-02-07, 01:46 AM
#7
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I also typed up that same howto in a wiki: http://www.rotorwiki.com/index.php/S4_OMP_Rebuild
wtfdidusay82: Please read the entire FAQ, and every link in my signature. I see a lot of questions from you that are posted elseware. I'll be pre-emptive and just tell you to read everything.
wtfdidusay82: Please read the entire FAQ, and every link in my signature. I see a lot of questions from you that are posted elseware. I'll be pre-emptive and just tell you to read everything.
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02-02-07, 10:42 AM
#8
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A die is a tool that puts threads on a rod.
The endplates of the OMP have an oval o'ring . Actually the o'ring isn't on the end plates but on the body where the endplates attach. Those oval o'rings are not available to be bought. Mazda does not stock them or know a darn thing about them (guessing a bit here).
So reusing the oval o'rings IS and option if you clean the area and apply a smear of RTV to them prior to reinstalling them. REmember,there is NO pressure to blow them out.
Reuse the o'ring that goes b/t the front cover and the OMP. It should not leak. Hasn't been there long enough to be bad.
The clearance for the OMP and rod is shown in the FREE AND ONLINE FSM for the series four cars. Either in the Lubrication section or possibly the ENGINE section.
Some JPGS attached to this :
The endplates of the OMP have an oval o'ring . Actually the o'ring isn't on the end plates but on the body where the endplates attach. Those oval o'rings are not available to be bought. Mazda does not stock them or know a darn thing about them (guessing a bit here).
So reusing the oval o'rings IS and option if you clean the area and apply a smear of RTV to them prior to reinstalling them. REmember,there is NO pressure to blow them out.
Reuse the o'ring that goes b/t the front cover and the OMP. It should not leak. Hasn't been there long enough to be bad.
The clearance for the OMP and rod is shown in the FREE AND ONLINE FSM for the series four cars. Either in the Lubrication section or possibly the ENGINE section.
Some JPGS attached to this :
Last edited by HAILERS; 02-02-07 at 11:10 AM.
02-02-07, 02:07 PM
#9
I just cleaned off the spot where all the oil was, and i rubbed my finger across the bottom of the omp underneath it and there was oil on my finger after...so i think the omp may probably be the problem, or at least part of it (oil pan leaks a little too).
I replaced the oring that mates along the block, so what would be leaking ? Im just not sure since I replaced the oring that goes to the block (i thought that would stop the leak before but it hasnt).
I replaced the oring that mates along the block, so what would be leaking ? Im just not sure since I replaced the oring that goes to the block (i thought that would stop the leak before but it hasnt).
02-02-07, 02:28 PM
#11
Youre right, I just cleaned it off and took it for a drive for about 10 mins or so after warming it up.
I got back and checked for any oil and there was no visible oil, but as soon as i put my fingers on and around the spot where the lever is I got oil on my fingers.
So without a doubt this is whats leaking, how long you think it would take someone completely unknowledgable with taking apart the omp to rebuild it ?
I was considering buying another one just incase it takes longer than I expect, just so I wont have to keep my car down.
The oil leak isnt really even that bad though, the disptick registered at halfway after about 800 miles on an oil change when I noticed the leak.
Aaron cakes told me half way on the dipstick means youre only missing half a quart of oil though ?
I thought half way on the dipstick meant you are missing half your oil (2 quarts or so), but I stand corrected by Aaron Cakes if it was only 1/2 a quart low, because half a quart isnt much...and i thought after about 1000-1500 miles (not sure) you burn about a quart of oil.
I got back and checked for any oil and there was no visible oil, but as soon as i put my fingers on and around the spot where the lever is I got oil on my fingers.
So without a doubt this is whats leaking, how long you think it would take someone completely unknowledgable with taking apart the omp to rebuild it ?
I was considering buying another one just incase it takes longer than I expect, just so I wont have to keep my car down.
The oil leak isnt really even that bad though, the disptick registered at halfway after about 800 miles on an oil change when I noticed the leak.
Aaron cakes told me half way on the dipstick means youre only missing half a quart of oil though ?
I thought half way on the dipstick meant you are missing half your oil (2 quarts or so), but I stand corrected by Aaron Cakes if it was only 1/2 a quart low, because half a quart isnt much...and i thought after about 1000-1500 miles (not sure) you burn about a quart of oil.
02-02-07, 02:33 PM
#12
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I doubt that lever is losing any appreciable amount of oil.
I generally figure that if I can do something, ANYBODY can do it.
That's about all I can say about the OMP.
I generally figure that if I can do something, ANYBODY can do it.
That's about all I can say about the OMP.
02-02-07, 02:39 PM
#13
Originally Posted by HAILERS
I doubt that lever is losing any appreciable amount of oil.
I generally figure that if I can do something, ANYBODY can do it.
That's about all I can say about the OMP.
I generally figure that if I can do something, ANYBODY can do it.
That's about all I can say about the OMP.
So anyone may be able to do it, but I doubt many people have the experience you do.
02-02-07, 02:45 PM
#14
Your pic shows to replace the oring in a different spot than the spot that the writeup says, ill show you a pic to show you where the oring goes according to the writeup. (unless there are 2 orings here, but i believe theres only 1)
Unless im thinking the part he put the oring on isnt the same part as the one youre pointing to in that pic, the orings you show dont look big enough to put on that spot on the lever/omp.
Also is there any certain way you have to put it back together like a certain way or order ? I dont want to put it back in and have it not working.
Unless im thinking the part he put the oring on isnt the same part as the one youre pointing to in that pic, the orings you show dont look big enough to put on that spot on the lever/omp.
Also is there any certain way you have to put it back together like a certain way or order ? I dont want to put it back in and have it not working.
Last edited by wthdidusay82; 02-02-07 at 02:54 PM.
02-08-07, 03:34 PM
#15
I just started this job and it has been quite frustrating. 
There seems to be way more parts inside the omp than shown in any of the pics, and putting it back together is harder than i thought.
I ended up losing my 10mm wrench have yet to find it and also stripped the threads on one of the screws to the endplates but got it off.
Anyone have some better pics and instructions on how this omp goes back together ? Ive got some pieces im in question as to how they all go back together.
My car is going to be down for the time being with the omp taken off, should I be covering the spot where the omp is with something , or will nothing get in there ?
Edit -
If anyone doesnt want to help or wants to flame on me , I'll admit I didnt do what I was suppose to.
I took it all apart and didnt pay attention like I should have to how it was coming apart because I figured it was going to be easy to put back together but turns out its not as easy as I had expected.
Theres this one little orangish colored part that has a little head on the top of it that isnt shown in any of the pictures, if I put it in I'm guessing at how its going back in and dont want to do that.
I can take a picture of all the pieces taken out and show a pic of this piece....this piece actually believed to fall on the floor when I took it apart (could hear it hit the floor)...and yes I know stupid.
There seems to be way more parts inside the omp than shown in any of the pics, and putting it back together is harder than i thought.
I ended up losing my 10mm wrench have yet to find it and also stripped the threads on one of the screws to the endplates but got it off.
Anyone have some better pics and instructions on how this omp goes back together ? Ive got some pieces im in question as to how they all go back together.
My car is going to be down for the time being with the omp taken off, should I be covering the spot where the omp is with something , or will nothing get in there ?
Edit -
If anyone doesnt want to help or wants to flame on me , I'll admit I didnt do what I was suppose to.
I took it all apart and didnt pay attention like I should have to how it was coming apart because I figured it was going to be easy to put back together but turns out its not as easy as I had expected.
Theres this one little orangish colored part that has a little head on the top of it that isnt shown in any of the pictures, if I put it in I'm guessing at how its going back in and dont want to do that.
I can take a picture of all the pieces taken out and show a pic of this piece....this piece actually believed to fall on the floor when I took it apart (could hear it hit the floor)...and yes I know stupid.
Last edited by wthdidusay82; 02-08-07 at 03:59 PM.
02-08-07, 04:15 PM
#17
Originally Posted by micaheli
Get a new 10mm wrench? 
They are like what... a couple bucks? Your car must not be that important to you.
They are like what... a couple bucks? Your car must not be that important to you.I have no way to go buy another wrench if I cant drive my car, right now!
I am hoping it will turn up soon , but I am not looking because it just gets me angry because I cant find it.
The pieces going back together on the omp though, I plan on taking a pic showing how i think it goes together to see what you all say. I want to make sure its 100% right.
My car must not be important to me ? Thats a very judgemental statment for someone who doesnt know the history of the car and myself but thats no big deal.
Ive actually had it for a little over 2 years and I've put over $5000 investing into repairs/mods, along with doing 90% of the work all myself and having said that I've only put 2500 miles on the engine since it was installed after the rebuild so what makes you think my car isnt important to me.
02-08-07, 05:25 PM
#19
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I don't remember any of the parts having paint on them much less orange paint.
I MIGHT post a jpg of the order of how the parts go on...tomorrow or very late tonight.
https://www.rx7club.com/forum/attach...hmentid=219608
About my jpg. It wasn't meant to show the order of how things go together, just the parts.
BUT, let's try something. First of all I'm going to call some part the FRONT and some the REAR. Front will be the part towards the front of the car and REAR toward the rear of the car. Common sense but sometimes not so common.
You have a plate at each end held with two screws. The plate with that is flat on both sides goes to the front of the OMP. The other plate goes......yes, on the other end. You knew that.
Then you have the two cylinders that go inside. They mate together in a sense. One has a slot and the other a male piece that fits in the slot.
From the FRONT of the bore in the housing, insert the cylinder with the grooves in it. That cylinder on its aft end should have a male piece that will mate with the slot in the other cylinger. So install that cylinder with the *mating* piece facing fwd.
Now install the second cylinder with the slot going in the cylinder first so it mates with the first cylinder.
At the fwd end of that second cylinder is a hole. Into that hole goes the rod with the spring around it.
Then the last thing is the front end cap.
BUT don't install the front end cap yet. Before you do that, install the lever into its hole. you'll have to shove the two cylinders fwd a bit so the lever will enter its hole.
Once the lever is installed, shove both cylinders fully aft and then install the front end cap.
Then install the aft end cap.
The cylinders go into the bore just like I have them in the jpg attached. That's about the only thing that is in order in that picture.
Also, on the side of the OMP that mates with the front cover is the drive gear. A worm looking drive gear. You should be able to manipulate it into its bore with the other components already installed. Don't use brute force, just wiggle and jiggle.
I left out the part on how to install the return spring on the lever. In my opinion that is an ART. I usually install that spring about the same time I install the lever in the body. I have to usually move the lever around to get the spring where it belongs. I really don't have the ability to tell someone how to install that spring the right way. Sorry 'bout that.
Maybe a jpg tomorrow.
EDIT: I noticed that I have the end caps in my picture just opposite where they go on that body in the jpg. Take note of that.
And the lever should have been shown at the bottom of the jpg, not at the top.
I MIGHT post a jpg of the order of how the parts go on...tomorrow or very late tonight.
https://www.rx7club.com/forum/attach...hmentid=219608
About my jpg. It wasn't meant to show the order of how things go together, just the parts.
BUT, let's try something. First of all I'm going to call some part the FRONT and some the REAR. Front will be the part towards the front of the car and REAR toward the rear of the car. Common sense but sometimes not so common.
You have a plate at each end held with two screws. The plate with that is flat on both sides goes to the front of the OMP. The other plate goes......yes, on the other end. You knew that.
Then you have the two cylinders that go inside. They mate together in a sense. One has a slot and the other a male piece that fits in the slot.
From the FRONT of the bore in the housing, insert the cylinder with the grooves in it. That cylinder on its aft end should have a male piece that will mate with the slot in the other cylinger. So install that cylinder with the *mating* piece facing fwd.
Now install the second cylinder with the slot going in the cylinder first so it mates with the first cylinder.
At the fwd end of that second cylinder is a hole. Into that hole goes the rod with the spring around it.
Then the last thing is the front end cap.
BUT don't install the front end cap yet. Before you do that, install the lever into its hole. you'll have to shove the two cylinders fwd a bit so the lever will enter its hole.
Once the lever is installed, shove both cylinders fully aft and then install the front end cap.
Then install the aft end cap.
The cylinders go into the bore just like I have them in the jpg attached. That's about the only thing that is in order in that picture.
Also, on the side of the OMP that mates with the front cover is the drive gear. A worm looking drive gear. You should be able to manipulate it into its bore with the other components already installed. Don't use brute force, just wiggle and jiggle.
I left out the part on how to install the return spring on the lever. In my opinion that is an ART. I usually install that spring about the same time I install the lever in the body. I have to usually move the lever around to get the spring where it belongs. I really don't have the ability to tell someone how to install that spring the right way. Sorry 'bout that.
Maybe a jpg tomorrow.
EDIT: I noticed that I have the end caps in my picture just opposite where they go on that body in the jpg. Take note of that.
And the lever should have been shown at the bottom of the jpg, not at the top.
Last edited by HAILERS; 02-08-07 at 05:52 PM.
02-08-07, 05:31 PM
#20
Originally Posted by HAILERS
I don't remember any of the parts having paint on them much less orange paint.
I MIGHT post a jpg of the order of how the parts go on...tomorrow or very late tonight.
I MIGHT post a jpg of the order of how the parts go on...tomorrow or very late tonight.
edit - this pic shows where i believe this piece goes and where it is i point out to.
02-08-07, 05:55 PM
#21
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Originally Posted by wtfdidusay82
The part looks like maybe its brass , I could take a pic of it but if you take the pic of everything it should be there.
edit - this pic shows where i believe this piece goes and where it is i point out to.
edit - this pic shows where i believe this piece goes and where it is i point out to.
I edited my post just above this one. You might read it again. About the jpg you attached. I don't know. I'll look at a pump late tonight and see what I can see.
02-08-07, 06:13 PM
#22
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Does the piece look like this? https://www.rx7club.com/forum/showth...ight=OMP+DRIVE
02-08-07, 09:02 PM
#23
No , its just a flat metal piece with a spot that comes up in the center. I could try to get a pic soon...this piece actually fell on the floor when i was taking it apart I heard it hit the floor, I'm 99% sure this came off something from the omp when i took it apart.
Oh and I just found my 10mm wrench now thats its 10:00 at night lol.
If you could , make a picture of how its suppose to go together.
I'll finish the work tommorow after I pick up some a new crush washer ( i didnt have one on there in 1 spot donno why..(or is better to just replace them all , i doubt it cost much for them maybe 25cent each.
I also need to pick up more brake cleaner to clean the parts with too, then we'll see how this goes and I'll upload a pic.
My main concerns are just not putting anything together backwards or the wrong way. Want to make sure its 100% the way its suppose to be before I go and put it on.
Oh and I just found my 10mm wrench now thats its 10:00 at night lol.
If you could , make a picture of how its suppose to go together.
I'll finish the work tommorow after I pick up some a new crush washer ( i didnt have one on there in 1 spot donno why..(or is better to just replace them all , i doubt it cost much for them maybe 25cent each.
I also need to pick up more brake cleaner to clean the parts with too, then we'll see how this goes and I'll upload a pic.
My main concerns are just not putting anything together backwards or the wrong way. Want to make sure its 100% the way its suppose to be before I go and put it on.
02-09-07, 12:05 AM
#24
Flat piece is a circle shape and thin, bronze/copper color and has a C letter in the center on one side and a little tip of the center sticking up on the other side.
Right now it is inside the spot/hole where the omp meets the block all the way inside with the C facing up where you can see it (other side has little tip in center sticking up).
Can take a pic if I need to show you, I am not very good at explaining.
Right now it is inside the spot/hole where the omp meets the block all the way inside with the C facing up where you can see it (other side has little tip in center sticking up).
Can take a pic if I need to show you, I am not very good at explaining.