Rb26 Throttle Body Seals

[GeeTR]

Hey,

I have a intake leak somewhere around my last throttle body runner. Brake cleaner sprayed on the last return spring, that sits around the spindle, would cause the motor to pick up the lazy cylinder and idle smoothly.

Thinking it must be the spindle seal, iv removed all the TB's and found myself a problem; I cant seem to source the seals ( show in picture attached ) Iv gone to a few local specialty seals places, and have found ones similar, though they aren’t made of viton, hence fuel resistant. I’m currently waiting on a quote for 500 custom made viton seals.

Has any one had any luck sourcing these seals, as Nissan want over $3K for 3 brand new TB's.

I’m almost temped to replace them with non fuel resistant ones, as the race bearings that the spindles sit on are a pressed in sealed unit as well ( and actually probably do most of the sealing )

The leak in the end, I think might have been due to loose rear plenum bolts, those last 3 pr1cks underneath as I could see blackening of the plenum >> TB gasket and the brake cleaner would have entered THERE under idle vacuum.

I’m running out of options, thanks guys!!!!

- Michael

[CruiseLiner]

search around for a second set of tb's for a couple of hundred bucks at the most if thats the part u reckon is leaking. have u checked nissan to see if they have some sort of seal to replace in that part of the tb? ive never heard of them leaking from the rear only the gasket surface areas

[GeeTR]

search around for a second set of tb's for a couple of hundred bucks at the most if thats the part u reckon is leaking. have u checked nissan to see if they have some sort of seal to replace in that part of the tb? ive never heard of them leaking from the rear only the gasket surface areas

I’m put off buying new tb's if i can just source half a dozen $2 seals. Nissan wont sell the seals, at the least, you need to buy 3 new tb's!

Yourself Google and this SAU's search button are hinting to me that a leak here is very rare, and possibly I was correct with the gasket leak then Hrrrrrrm. *ponders*

thanks for your thoughts Cruise

- M

[godzl1975]

if your looking for throttle body gaskets then nissan do sell them! individually as well...recall were 5 dollars for each throttle body. you will need 3 so $15.

[CruiseLiner]

nah hes talking about on the end of the throttle shaft that go into the side of the tb's not the gasket surfaces.

check out the pics and it shows ya which section he means

[Duncan]

I am pretty sure you will find it was just a gasket leak....put it all back, got those 3 bastards torqued up right and you should be fine.

[GeeTR]

I am pretty sure you will find it was just a gasket leak....put it all back, got those 3 bastards torqued up right and you should be fine.

Yup, that’s what im hoping, and worst case, that’s what im doing. Wanted to see if anyone’s heard bout this before, just in case there’s a similar seal made for ... cappuccino machines or pool chlorinators

Thanks Duncan

[Godzilla32]

I have had leaks from the mating surfaces due to bad contact. It sounds like birds chirping away in there! Make sure you have competely removed the old gasket material. Any left will create a leak. Use a razor blade to scrape it off being careful not to take a chunk out of the soft alloy. Nissan sell the gaskets for 3 dollars each.

[Sydneykid]

Personally I have never had a throttle shaft air leak on an RB26. It is usually the TB to inlet manifold gasket or the inlet manifold to head gasket. The most common problem is dowels the not lining up or bottoming out.

The bottoming out occurs when we have machined the gasket surfaces flat, without maching the dowels suitably. I have also seen too long bolts and/or bottomed out studs cause similar problems.

cheers

[GeeTR]

Personally I have never had a throttle shaft air leak on an RB26. It is usually the TB to inlet manifold gasket or the inlet manifold to head gasket. The most common problem is dowels the not lining up or bottoming out.

The bottoming out occurs when we have machined the gasket surfaces flat, without maching the dowels suitably. I have also seen too long bolts and/or bottomed out studs cause similar problems.

cheers

Thanks SK,

145 views of my thread, and no one has even heard of a TB spindle issue?

Exxcellent

Cheers!

- Michael

[GeeTR]

This seems to be the only thread on this topic, so ill continue to update till its solved

I went back to the place that could sell the non viton, similar shaped seal, Capital Bearings here in Fyshwick Canberra.

PBR 12377-

Unfortunately they are too tall by a good 3mm, are too tight a fit on the outside, and grip the spindle too tightly, im screwed on all fronts.

You can see in one of my photos there’s actually a spring around the inside sealing surface.

I’ve decided to leave the rest of the seals, just figure out a way to seal the ones, iv already played with.

I was thinking some nylon rod in a lath, some grooves, some o-rings…

There must be a seal somewhere that I can use, I might try overseas

- M

[blur]

i thought i had a leak on my t-bodies once, seemed to pick up idle speeed when spraying the throttle shafts... ended up being the gasket between the head and the first part of the manifold. leaking at the back on number 5&6. was a bit more involved to remove, but sure did fix the problem. are those seals still soft, maybe reuse them and spray some silicone spray on to them to soften it up.

[GeeTR]

i thought i had a leak on my t-bodies once, seemed to pick up idle speeed when spraying the throttle shafts... ended up being the gasket between the head and the first part of the manifold. leaking at the back on number 5&6. was a bit more involved to remove, but sure did fix the problem. are those seals still soft, maybe reuse them and spray some silicone spray on to them to soften it up.

Hey Blur,

Yah, i actually think the leak is / was from the plenum to TB gasket, as there’s some black discoloration on the matting surface, as well as a distinct lack of ppl on this forum hearing of the issue.

My issue now is that I need to at least fix the seals i plucked outa the rear TB; that’s what these PBR seals where meant to fix.

Ditto on reusing, i destroyed them getting em out.

Thanks bud

M

[Sumo]

Altenators use some different types oil seals for their vacuum pumps on diesels.

I dont have the books to look them up no more tho. If you had some seal sizes, it might be worth giving ashdown ingrams a ring.

Cheers

Sumo

[CameronBNR32]

I had the exact same when I first put my new motor in the car. It was a 'High Pitched Squeel' coming from number 5 and 6 throttle body.

I pulled off the whole plenum, replaced all the plenum to throttle body and throttle body to head gaskets with new ones and it was fixed 100%

The ones you get from Nissan now are thick 'organic'? ones, not like the oringinal thin metal ones.

Edited December 9, 2006 by CameronBNR32

[GeeTR]

Well kids, newest installment.

Iv used some 800 wet&dry and sanded the seal down 3mm, iv then wrapped a rod ( the same diam as the spindle) in W&D and sanded the inside contact surface to relieve the tightness on the inside.

Lubed it all, pressed it in and manually moving the throttle plates gives the same amount of tension as the un modified ones!

Dummied it all up, and Bingo, a lot less throttle peddle tension.

Side Note:

There still was a lot of tension, and i found one of the rose jointed ends on the rods connecting to each spindle was seized. Carby cleaner and soaking in automotive mineral oil for 48h did little. Tonight i played with the movement a little and noticed the socket was only grabbing the sphere in one plane of movement... like it was "oval" shaped A dozen gentle smacks with a hammer has the sphere moving fine again! So Note to rem, if your rose joint is grabbing, make sure the socket hasn't distorted out of shape

Once my POS Datsun has fired back up, i will finally know if this has curred my leak

Hope this helps someone else

Mods: Maybe move this to the Maintenance section

[h2k]

I have the exact same problem with air leaking trough the throttle shaft gasket, but on a Q45 90mm throttle body. When it starts squealing at 0.6 bar pressure and at 0.9bar pressure the squeal is so high-pitchet I have to hold my ears. Really annoying! So I've ordered a new tb, I havent found a way of replacing those red seals on the shaft

[GeeTR]

I have the exact same problem with air leaking trough the throttle shaft gasket, but on a Q45 90mm throttle body. When it starts squealing at 0.6 bar pressure and at 0.9bar pressure the squeal is so high-pitchet I have to hold my ears. Really annoying! So I've ordered a new tb, I haven't found a way of replacing those red seals on the shaft

Hey Sindre,

Get your digi camera in Macro mode onto the seals and let us have a look! Technically, i still had a lot of options with mine. I could have ground out the little press tabs, and pulled the sealed bearing from the unit. In the end, replacing the outside dust seal worked.

Cheers

[h2k]

Hey Sindre,

Get your digi camera in Macro mode onto the seals and let us have a look! Technically, i still had a lot of options with mine. I could have ground out the little press tabs, and pulled the sealed bearing from the unit. In the end, replacing the outside dust seal worked.

Cheers

So you found a part nr for the outer dust seals? I took the tb apart as much as I could but I could not figure out how to remove the axle and the read seals. So I drippet a couple drops of superglue in the red seals and refitted the tb, and set my boost down to 0.6bar so it doesnt leak so much while I wait for the new tb I've ordered. but when I change tb's and take the one with a leak out I can take som macro pictures of it. Im hoping the new tb come in the mail today or monday.

[GeeTR]

So you found a part nr for the outer dust seals? I took the tb apart as much as I could but I could not figure out how to remove the axle and the read seals. So I drippet a couple drops of superglue in the red seals and refitted the tb, and set my boost down to 0.6bar so it doesnt leak so much while I wait for the new tb I've ordered. but when I change tb's and take the one with a leak out I can take som macro pictures of it. Im hoping the new tb come in the mail today or monday.

The infamous h2k - Hey mister, i seen your Dubai vids on uTube, you guys are using up all our stocks of parts dammit! Get your grindy grindy on, rip the seals out, and source replacements! Jesus, you "no tax" guys are wiping us up!!!

... jk - kinda

Edited May 16, 2007 by GeeTR