Good morning everyone,

I noticed a leak coming from right under where the shift boot is. What is the usual suspect for this leak?

leaks tend to start one place and then seek the lowest point. It could be a transmission leak or and oil leak from the engine working back.

Transmissions often leak around the speedo drive. Could also be coming from the top of the trans where the shift lever stabs in. O rings and seals fix both. the speedo is easy to get at, the top transmission leak not so much.

IF its engine oil just getting blown back and then leaking its prob from a rear main seal.

Is there ANY oil dripping right at the front of the trans bell housing/rear of engine area?

If leaks bother you, the correct fix would be to pull the trans get all the seals replaced (front/back/speed/shift striker rod), while there replace the throw out bearing/clutch/rear main/and rear main bearing cap seal and pan gasket.

Bottom line is its going to leak unless those seals have been replaced  since new.

if that sounds like too much, then clean the area real well with brake cleaner, get it dry, then drive a little and get up real close to narrow down the problem. could be one  of the above or several.

Edited May 15, 20195 yr by Dave WM

3 hours ago, BayAreaZ650 said:

Good morning everyone,

I noticed a leak coming from right under where the shift boot is. What is the usual suspect for this leak?

 

There was just a few posts about this on the forum somewhere.  The striker rod seal hardens up/wears out,  and leaks, apparently.  One possibility.  Hard to fix.

 

4 hours ago, Dave WM said:

leaks tend to start one place and then seek the lowest point. It could be a transmission leak or and oil leak from the engine working back.

Transmissions often leak around the speedo drive. Could also be coming from the top of the trans where the shift lever stabs in. O rings and seals fix both. the speedo is easy to get at, the top transmission leak not so much.

IF its engine oil just getting blown back and then leaking its prob from a rear main seal.

Is there ANY oil dripping right at the front of the trans bell housing/rear of engine area?

Good call, it's leaking at where the shift lever goes in. Where would be a good place to source the O ring for it?

There are a few drops coming from the area where the engine and transmission meets as well.

1 hour ago, BayAreaZ650 said:

Good call, it's leaking at where the shift lever goes in. Where would be a good place to source the O ring for it?

There are a few drops coming from the area where the engine and transmission meets as well.

Nissan

Harbor freight has a transmission floor jack for $99.00.  it makes it so that you can remove the transmission by yourself with the car about 2 feet up on jackstands.  I did it this past winter to replace the clutch and rear main seal.  It helps to have an extra set of hands to line it up for re installation, however.  It becomes pretty apparent just how bad the rear seal can be leaking when the transmission is out of the way.  It's also a convenient time to replace the oil pan gasket(the transmission out of the car, that is).

 

https://www.harborfreight.com/450-lbs-low-lift-transmission-jack-61232.html

Looks like the o-ring is still around.  Not sure what transmission you have but they're probably all the same one.

http://www.carpartsmanual.com/datsun/Z-1969-1978/power-train/transmission-control

Here's a spendy one.

https://www.amazon.com/Nissan-32857-14600-Cap-O-Ring/dp/B01LY9R00E

1 hour ago, BayAreaZ650 said:

There are a few drops coming from the area where the engine and transmission meets as well.

Could be engine oil or transmission fluid.  Smell it.  Both require transmission removal though.  Might as well do them both.  Might as well replace your throwout bearing while it's out.  And the clutch is probably worn.  You'll be down by the slave cylinder too.  And its hose.  The transmission mount is probably worn out.  Pilot bushing.  Probably have to remove the exhaust system, check the gasket surface.  Might break a stud removing the pipe so that could be an issue.  If you have to remove the exhaust manifold you'll have the intake manifold off.  Might as well replace the injector seals.  Don't forget......

might as well...

:)

 

in all seriousness the might as well does happen, so you really have to assess your willingness to leave with a small leak. Just remember its a old car and the might as wells can really add up, including the follow up can or worms (broken studs etc....).

So are you a leave it be, enjoy driving more that fixing, or a drop of oil is going to make you nutz. OK to be either but you need to decide.

Also you will find that doing the work yourself is not just to save money but to make sure its done right unless you have a mechanic that really knows what they are doing and how to work on old cars.

I find the biggest issue is not breaking bolts. Technique helps but eventually you are going to break one in a hard to get at location that can up the work factor a lot.

You are going to have to do the clutch eventually anyway, it will chatter and slip etc... That is a good time to force you to fix other leaks. Just don't be surprised if you end up making some work for yourself along the way to fixing something easy (like breaking a bolt on the t stat housing when replacing a t stat...).

I like my induction bolt heater, pricey but comes in handy.

Edited May 16, 20195 yr by Dave WM

12 hours ago, Dave WM said:

might as well...

:)

 

in all seriousness the might as well does happen, so you really have to assess your willingness to leave with a small leak. Just remember its a old car and the might as wells can really add up, including the follow up can or worms (broken studs etc....).

So are you a leave it be, enjoy driving more that fixing, or a drop of oil is going to make you nutz. OK to be either but you need to decide.

Also you will find that doing the work yourself is not just to save money but to make sure its done right unless you have a mechanic that really knows what they are doing and how to work on old cars.

I find the biggest issue is not breaking bolts. Technique helps but eventually you are going to break one in a hard to get at location that can up the work factor a lot.

You are going to have to do the clutch eventually anyway, it will chatter and slip etc... That is a good time to force you to fix other leaks. Just don't be surprised if you end up making some work for yourself along the way to fixing something easy (like breaking a bolt on the t stat housing when replacing a t stat...).

I like my induction bolt heater, pricey but comes in handy.

You bring up an excellent point that I never really thought about. This is my first older car and I thought fixing all the little leaks would be worth it before working on the cosmetic portion (getting the Z painted). I think I can live with the little leaks but a part of me also wants to fix it. My fiancé and I have been doing all the work ourselves and it feels rewarding.

I think fixing the leak furthest to the left on the photo would make me happy enough. It sounds like the other leaks would require dropping the transmission which I’d be interested in learning how to do too. Would changing out the clutch and seals be something that someone with some mechanical knowledge be able to do?

Here's the list that we've changed/repaired:

• Drum Shoes/Resurface Drums

• Brake Fluid Flush

• Cold Start Injector

• Fuel Filter

• Transmission Fluid Change

• Oil Change

• Fuel Injector

• Spark Plugs/Spark Plug Wires

• Brake Rotors

• Wheel Studs

• Radiator Flush

• Reverse Switch

• Fuel Filter

• Shifter Bushing

This is the list of things we need to do:

• Differential Fluid
• Timing Adjustment
• Valve Adjustment
• Suspension (Worn)
• Bushings
• Leaks
• Turn signal switch
• Headlight switch