mech fuel pump spacer

[qz16]

I need a mechanical fuel pump spacer. There are two types that I know of a (2) bolt hole and a (3) bolt hole. I need the (3) bolt hole.  It is made from the same material that is used for the thermal insulators between the intake manifold and an SU carburetor. Thanks for your assistance.
 

[zKars]

The two bolt is for L4 engines. L6 uses the three bolt.

Rock Auto lists them, so they are likely available through a local autoparts store. Beck/Arneley part.

https://www.rockauto.com/en/catalog/nissan,1973,240z,2.4l+l6,1209170,fuel+&+air,fuel+pump+spacer,6252

If you really want a Nissan one, I can send you one if no one closer responds.

[qz16]

Thanks for responding.  Appreciate the explanation on the two bolt vs. the three bolt - thank you.  I've searched the web and also have been checking Rock auto, they continue to show out of stock.  Beck Arnley discontinued the part.  If  you can spare one I would really appreciate it - thank you.  I will send you a message with contact info.  Someone in mexico is selling the two bolt, 4 cylinder version, but I have not found anyone that is building these.  I have seen threads where folks have written about aluminum version but have not found any info to order one.

[zKars]

Glad to help, got your message. 

No surprise they are discontinued I suppose. I wouldn't use an aluminum one, I think the point is that they are heat insulators, something alumuminum is particularily poor at! 

[zKars]

Here is a picture. Even comes with a couple of gaskets

[zKars]

Details discussed in the PM. Let me know when you're ready.

[qz16]

Done deal.  Once again thanks for the help.  Like you I thought that one of the purposes of the spacer was for thermal insulation.  But, someone pointed out that the bolts go directly from the pump into the head, so I have come around to thinking that the primary purpose is to properly space the pump from the eccentric.  Once again very nice of you to help out.

regards,

ron

[motorman7]

It's a moot point since you have the insulator, but yes, the insulator is for heat insulation.  Even though the bolts provide direct heat transfer, the transfer Area is reduced by using the insulator.  This can be seen in the equation:  for heat transfer.  A is area, delta T is difference in part temperatures (head versus fuel pump)  and Delta X is the length of the bolt through the insulation.  k is the thermal coefficient of the bolt.  If you use titanium bolts, this number would be very low, copper would be high.  Steel is in the middle somewhere.    This equation then becomes a battle between how much the air in the engine compartment cools the fuel pump versus how hot the head is.  The heat battle is going on through the bolts that connect the two. The reduced transfer area helps the pump stay a bit cooler due to the reduced area as the equation shows.  I am sure @Zedyone_kenobi would concur and he is a rocket scientist.

Just my two cents.

Best regards,

     Rich

PS: I only weighed in on this because i was trying to find the pump insulator myself a week ago.  They are becoming quite rare it seems.

Edited June 24, 2017 by motorman7

[qz16]

I learn something everyday - thanks.  Hope you found a spacer for yourself.

[motorman7]

17 minutes ago, qz16 said:

...  Hope you found a spacer for yourself.

Thanks, fortunately I did.  It's one of those things where I found the original a couple days after I gave up looking for it.  Lucked out.

[w3wilkes]

I've gone to an electric pump and while removing the mech pump I broke the spacer. The block off plate goes on fine without the spacer and I don't think heat transfer should be an issue for the block off plate. Since I'm saving the mech pump and mounting stuff the only spacer I could find was on ebay;

http://www.ebay.com/itm/like/202014972729?chn=ps&dispItem=1

But whoa, pretty spendy. I figured the only way I could ensure that I wouldn't need it down the road was to buy a new one!

[w3wilkes]

I know this thread is old, but I was over on Z car Depot and they have spacers for $10 if anybody needs one.

https://zcardepot.com/products/fuel-pump-spacer-plate-240z-260z?utm_source=beeketing&utm_medium=precommend&app=precommend#