Coolant leak from engine block

[etang789]

Found a cap on the engine block with some coolant leak.

Not sure if there is a gasket inside or O Ring or just simple gasket sealant? Can someone tell me which parts is needed or how to fix this can't find any diagram for this section...

 

[goldNSX]

I'm pretty sure there a seal behind it. Good luck removing the screws...I'd be very cautious...

 

[Old Guy]

That looks like it might be a fitting for one of the cylindrical block heaters that Honda uses. I wonder if anyone actually installed one on an NSX? If you plan to pop the cap off you better have the cooling system drained because it is pretty much going to empty out on top of you if that is the block heater plug.

I have never seen a genuine NSX block heater; but, if it is like the other Honda / Acura heaters of that cylindrical style, it actually threads into the hole and it seals with a metal crush washer much like on the oil drain plug. That cap obviously does not thread in so I don't know how it is sealed.

 

[cmc140]

That looks like it might be a fitting for one of the cylindrical block heaters that Honda uses. I wonder if anyone actually installed one on an NSX? If you plan to pop the cap off you better have the cooling system drained because it is pretty much going to empty out on top of you if that is the block heater plug.

I have never seen a genuine NSX block heater; but, if it is like the other Honda / Acura heaters of that cylindrical style, it actually threads into the hole and it seals with a metal crush washer much like on the oil drain plug. That cap obviously does not thread in so I don't know how it is sealed.

That cap is where the block heater mounts. My NSX had the factory block heater installed at the dealer. I removed it and bought that cap, which I believe had an o-ring, but I don't really remember.

 

[goldNSX]

The o-ring seems to be this one: 91301-PR7-A00. According to the parts catalog it is sold separately.

Be prepared to have a free shower even if you drain the coolant.

 

[Mac Attack]

Found a cap on the engine block with some coolant leak.

Not sure if there is a gasket inside or O Ring or just simple gasket sealant? Can someone tell me which parts is needed or how to fix this can't find any diagram for this section...
View attachment 157267

If you pop the cap off it has a machined insert with an o-ring that seals on the inside diameter of the block.

In this pic the axle is blocking a coolant drain adjacent to that cap, so you should be able to drain coolant through that fitting and then pop the cap off. Just be careful prying it out because it does sit inside the block with that o-ring seal. It may be a bit difficult to remove, but once the bolts are out you can try to rotate it to break the o-ring "stiction" and then try to pull it out.

 

[Mac Attack]

Ah, I found a pick of my engine block before it was cleaned/machined.

As you can see, that cap is a bit more substantial than it appears on the outside. It may take some fiddling to remove.
[MENTION=10201]goldNSX[/MENTION] gave you the part number for the o-ring!

View attachment 157284

 

[etang789]

The o-ring seems to be this one: 91301-PR7-A00. According to the parts catalog it is sold separately.

Be prepared to have a free shower even if you drain the coolant.

Thanks man!

Ordered the O-Ring and bolts and Cap just in case...

Ref No. 2 Acura Part No.: 91301-PR7-A00 O-Ring (28.7X3.5)
Ref No. 37 Acura Part No.: 95701-06018-08 Bolt, Flange (6X18)
Ref No. 2 Acura Part No.: 11105-PH3-000 Cap, Sealing (35MM)

 

[B2FiNiTY]

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