261 Chev Engine

William Spence (RIP) · #1 09-04-05, 20:38

I am up-engining a 1942 HUP from a 216 to a 261 engine as the 216 is only good for a boat anchor. The 261 is a full force-feed engine & alas I don't have any manuals or info re these engines. It is ready to be put back in the truck but I need info re the oil filter - this engine has one mounted on one of the manifolds but I can't see where the lines enter the block. There is one fitting below the filter at the bottom of the block, but I don't see where the other line goes. Can someone send me a picture of this side of the engine so that I can get this filter set up properly???? Many tks,

Bill Spence Mac Duff Piper

Phil Waterman · #2 09-04-05, 22:52

Here are a couple of web sites that you may find useful. I just found a 261 which will be delivered in the next week or so. So I will be following along on conversion to a 261, though I have had very good luck with the 216s.

http://chevy.tocmp.com/
http://www.55-57chevys.com/coccc/index2.html
http://www.stovebolt.com/
http://www.chevytrucks.org/
http://www.chevrolet.com.au/articles/engine_swap.htm

William Spence (RIP) · #3 11-04-05, 22:57

Phil, Tks for info re my query, the first site you gave me answered all my questions. Tks again. PS Am still working on dog-house doors. The prototype that they made for me looked pretty good although not an exact replica of the original. Still, it will still look better than an empty hole.
Will send you a pic when I get them (soon I hope).
Cheers, Bill Spence

Bob Carriere · #4 12-04-05, 22:34

Hi Bill

I will show you mine if you show me yours....?????

I have some side pictures of my rebuilt 261..... will need to send them from home.......

I intend to run two PH 8 twist on can filters on my cab 11 since there is no sufficient room in the engine compartment to install the original cab 13 oil filter can...... which is identical to the filter can found on M37 dodge . My cab 11 calls for the same M37 can filter to be installed sideways underneath the passengerside mounted inside the frame..... can you imagine the oil bath every time it is serviced.... I have opted for easier two modern filters for good filtration... cheap cost...... picked up the race stock car filter housing at a flea market for $10 bucks.... I beleive they are still available at car shows or even at Canadian tire.

While on the topic of 261..... are you planning to run the original Rochester 261 carb...... they are larger to accomodate the cc of the 261....... kits are avaialble from Carb King which can be found on Stovebolt site.... very helpful gentlemen...... I call him a gentle men since he sold me his last NOS 261 Rochester carb for my beastie...... whoops sorry Phil.... my cab 11.

I am considering installing a Pertronix inside the dist. to reduce maintenance to a bare minimum....... also have a case of original spark plugs AC45 if interested.......

Are you both planning to run the later larger flywheel/clutch inside your 216 bellhousing???? it fits... I know!!! the extra torque should really make sweet grinding music!!!!!

We may need to share ideas on the water pump clearance issue when we get to the final installation stages.....????

Stay in touch

Bob C.

William Spence (RIP) · #5 13-04-05, 00:30

Hi Bob: Tks for the lastest bumf on your re-build, I copied your article from MLU Up & have studied it closely. I hope to use the manifold mounted oil filter canister now that I have more info-it shud fit under hood of 13 Cab. I have had clutch rebuilt with original 216 flywheel to use with 216 starter, PATRICK'S says that it works fine on 12 volt. I was able to get an original rebuild kit for the CARTER W-I carb off the 216 as I didn't get a carb with this engine. I'll let you know if it works or not. I have bought a short-shaft water pump from PATRICK'S as the original is too long.
When you see this pump you'll find that it is just a rebuilt 235 or 261 pump with a cut down shaft & a pulley with a much smaller bell.. If we could find out where to buy these pulleys, we could save a lot of money on water pumps.
Pls keep in touch re ur engine & i'll do likewise.. No point in us both trying to re-invent the wheel!!!
Cheers, Bill Spence

Bob Carriere · #6 13-04-05, 16:55

Hi Bill

Your 216 W-1 carb will seriously restrict the output of the 261... in fact if you are using the original 261 manifold the bolt pattern should be wider/bigger than the 216 carb. You should be able to mount a Rochester "B" type carb and still used the 216 air breather.

On the water pump I shortened my own pump shaft and bought an after market shallow pulley from Canadian tire..... part of the problem is if I shorten the pump shaft to the max the original five blade fan of the 261 will hit the lower damper pulley..... I may not be able to fully resolve until I get my radiator back for the shop being recored.

Let's work on this together..... besides Phil is always good for a trick or two.

Later dude.

Tony Smith · #7 13-04-05, 23:53

There's a guy on e-bay who often has adapter plates to fit the original Off-the-shelf 216 water pump to a 235/261 block, thus getting around the need to buy a special modified pump. His instructions say you will need to drill and tap two new threads into the 235/261 block. He doesn't appear to have any listed at the moment, but keep an eye out. Who knows, you might have the know how to do this yourselves?

Tony Smith · #8 14-04-05, 00:44

... there is an adapter plate listed on e-bay now.

William Spence (RIP) · #9 14-04-05, 17:20

Tony, Tks for heads up re adaptor plate to use 216 water pump on 261 engine. The main problem that I see here is that the small pulley on the 216 pump vs the large pulley on the 235/261 pump will cause that pump to turn so fast that it will starve the engine from coolant and then, more bad news, an engine seizure could follow. The 216 pump only gets it coolant from a hose, whereas the 261 pump fits right into the block & has lots of coolant to spread around. This would be OK for short runs before the engine gets really warmed up, but I wouldn't want to go for a longer run & chance an overheat & seizure.
Let me know if you know of anyone that has successfully used this adaptor plate without any overheating problems or if they have found a larger pulley to fit on the 216 pump to overcome this problem. Also, let me know if you have heard of an adaptor plate to use a 216 Carter W-l carb on the 261 manifold. I had one professionally rebuilt at a cost of slightly over $150 Cdn before I decided to scrap the 216 engine & go to a 261, but the 261 didn't come with a carb.

Many tks, Bill Spence MacDuff Piper

Mike Kelly · #10 19-04-05, 18:14

A word of caution may be useful .

CMP's like the HUP were designed by engineers who knew that the average road speed with the 216 would be around 40-45 MPH . If you install a later 261 or whatever donk , you will almost double the bhp available (85 vs 145) . Your HUP with its higher revving 261 engine will cruise along at say 55 mph , easily . Remember these vehicles have a short wheelbase and high centre of gravity . Even the slightest wobble at that speed may have distastrous effects . Imagine a tyre blowout .....

The 216 fitted with aluminum pistons and modern slip in big end bearings is another way to go . Parts for the 216 are readily available still .

Mike

William Spence (RIP) · #11 19-04-05, 22:59

Mike: Tks for heads-up re possible disasters re over-powering a HUP. I plan to build this truck as the New Zealand C8AX, with a towing pintle so that I can tow an armoured scout car such as a Dingo or Ford Lynx either on a trailer or on a tow bar. Either way, the 216 would not have enough power to handle a 6000 lb tow. Also, the 216 that came with the truck was a piece of junk with mis-matched head, broken piston, crankshaft damage & a set of accessories that looked like refugees from the junk-man's yard. With this pile of scrap metal to start with, it made the decision to re-engine necessary, so a larger engine will solve both problems. However, thanks for the safety tips & I will keep these in mind when driving without a tow behind. Hopefully that should be sometime in this century.
P.S. Would appreciate some pix of the various bodies that were put on the back of the C8AX besides the 8 cwt GS body.

Cheers, Bill Spence

Phil Waterman · #12 19-04-05, 23:11

Mike you are so right when you say "A word of caution may be useful … CMP's like the HUP were designed by engineers who knew that the average road speed with the 216 would be around 40-45 MPH ."

My HUP with brand new tires and a good running 216 will travel down the road at 45 MPH without undo noise or vibration. Above that speed all those large heavy spinning shafts and parts start telling you that they are getting unhappy ie noise and vibration. The bigger advantage of the re-engining should be expected to be in the ability to maintain that speed going up hills in traffic.

I suspect that slow moving trucks on long up grades is something that most of us grew up with, but with the increase in truck power on big rigs people have less patience.

Other words of caution would of course be related to braking and breaking. Though HUPs for there day have very good brakes you still have nearly 3 tons of truck going down the road on less road contact than a subcompact. The other breaking is breaking drive train components, having now broken both rear axle shafts with just the original horse power care of the application of power comes to mine.

Having said all of this I’m waiting for my 261 full pressure Chevy truck engine to be delivered.

Hanno Spoelstra · #13 24-04-05, 21:58

Quote:

Originally posted by William Spence
I plan to build this truck as the New Zealand C8AX, with a towing pintle so that I can tow an armoured scout car such as a Dingo or Ford Lynx either on a trailer or on a tow bar. Either way, the 216 would not have enough power to handle a 6000 lb tow.

William, looking up the "Recommended maximum gross laden weight of full trailers when towed by load carriers with full load", I don't see the C8A listed. Depending on exact type, the CMP 15-cwt was supposed to tow 3 tons on normal roads maxiumum, quoted weights for hilly roads and cross country are lower of course. Further to Mike's word of caution, I'd like to add the engineers who designed the C8A did not design it with it having to tow any load in mind. My guess is you'll be breaking half shafts like there's no tomorrow and stopping a road train consisting of a C8A and an unbraked armoured scout car will be a hazardous operation at any speed

Hope this helps,
Hanno

William Spence (RIP) · #14 24-04-05, 22:14

Hanno: I am building the New Zealand C8AX- 8 cwt which is on a HUP chassis & does have a towing pintle on it. Regarding a "ROAD TRAIN" runaway, over here trailers towing over 3500 lbs have to have electric brakes on them to prevent the problem you mention. The tow is not intended for cross-country work, it is merely to get 2 vehicles to shows without having to drive both on the highway or rely on drivers behind the wheel of one of your vehicles who don't give your vehicles the proper treatment that you feel your vehicles deserve. However, thanks for your concern.

Cheers, Bill Spence

Phil Waterman · #15 24-04-05, 23:06

As far as I can find HUPs were not intended to have a pintle. Having said that I've seen many photos of HUPs with trailers generally of the 1/4 ton size. I think Bart Vanderveen’s HUP had one. From the pictures, it looks like the common Jeep pintle was often fitted though this would require reinforcing the rear frame member. According to the service bulletins, they had to reinforce the tow rings 2" holes in the frame rail ends because they tore out.