Chev 216 loose piston pin - which one ?

[Phil Waterman]

Hi Mike

All three of my 216 engines still have their original carbs all are Carter W-1 but they are not identical there were changes during the years of production. Carb at left is out of the 41 Pattern 12 one at right is the 1945 HUP carb.

Web Carb early and late W-1.jpg

Yes, I have noted that all of the engines seem to run richer, than when I first started driving them years ago. Do not know if this is the carbs or if it is that the gasoline has change a lot in the US.

The HUP with 216 has original oil bath, C60L with 235 has a 235 oil bath (throat is bigger) the C60S with the 261 has a modern paper filter could not find an oil bath that would fit the carb or the space.

The Carter W-1 on the HUP has been trouble free in 37 years of driving except for one time when I got a half a tank of water at a gas station. Ended up fixing the truck on the side of the road, drain the filter, remove the fuel bowel on the fuel pump, took the top of the carb and empty the water out . Fortunately I had only filled one tank at that station so was able to switch over to the other tank, then with the fuel line disconnected from the carb pumped the hand primer on the fuel pump until the lines were clear and gas going into the collection can was clear.

Because of the ethanol in the US gas I have discontinued using the mechanical fuel pumps on two of the trucks and replaced them with 6 volt electrics. On the HUP the original fuel pump is still in place and the fuel goes through it but it has a metal plate where the pump diaphragm would be used galvanized steel so it should not rust.


The two bigger trucks with the 261 and 235 engine have the correct carbs for the truck engine, got lucky and found the pair on e-bay NOS for under $50 US. Both were missing the same little check valve which is why they were still in the box as NOS because they didn't work correctly robbed the check valve from two non-functioning old carbs and they run great. Both are Rochester Carbs.

Web 261 235 216 Carbs.jpg

When I swapped engines on the 3 Tons I kept the original engines as complete units on engine stands, ready to reinstall should the need ever arise. Only thing missing fans and generators which moved over to the newer engines.

Cheers Phil

[Mike K]

The Rochester manual

http://www.newagemetal.com/pages/Ser...delBmanual.pdf

[Phil Waterman]

Hi Mike

Thanks for posting the link will print out copy put in my shop manual binder. The part that was missing in the two carbs I bought was the little ball part # 30 or 41. Only found that it was missing by matching every part with an exploded parts like the one in the manual you posted. In that case the poor parts and adjustment sheet that came with a carb rebuild kit.

Lesson I learned from that experience was if a carb doesn't work right and may have been disassembled, like " NOS " carb is make sure all the little bits are actually in correct place.

Again thanks

Cheers Phil

[Mike K]

The two hole 216 pump is identical to the single hole CMP pump...... apart from the backing plate. Is this correct ?

http://www.ebay.com.au/itm/Chevrolet...item4196e9e3fd

Mike

[motto (RIP)]

No Mike, the one and two hole pumps are quite different. I think that the only components they have in common are the moving parts. The bolt patterns are not the same and the angle of the inlet stub is also different. Put the two pumps side by side and it is immediately obvious.
The one hole pump is the same as on the GMC 270 CCKW engine but for the pulley.

Dave

[Grant Bowker]

I too found the one and two hole pump housings to be different. I tried to use the adapter plate intended for two hole pumps to put a 1 hole pump on a later (261) engine and ended up having to make my own adapter plate. The general outline is similar but not identical and only some of the bolt holes are in the same locations.

[Mike K]

Originally Posted by motto

No Mike, the one and two hole pumps are quite different. I think that the only components they have in common are the moving parts. The bolt patterns are not the same and the angle of the inlet stub is also different. Put the two pumps side by side and it is immediately obvious.
The one hole pump is the same as on the GMC 270 CCKW engine but for the pulley.

Dave

Ok thanks for that info

I found out that my Rochester Carby has been fitted to the inlet manifold of the 216 with the vacuum port to the power valve in the carby blocked off I need to modify the base mount to fix this problem

[Phil Waterman]

Hi Mike

Depending on the application and year they moved the vacuum tap around on the manifold. Is the manifold off the engine? If so I would just drill and tap the manifold near the carb. Do not try this directly under the carb as the heat riser brings the exhaust gases up in that big area.

Another alternative is make an adapter plate for under the carb and tap the vacuum through the side of the adapter. This is how they tapped the vacuum for the brake booster on some of the engines.

Take a look at http://www.canadianmilitarypattern.c...ifications.htm some vacuum tap locations.

Cheers Phil