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| | | | Joined: Nov 2009 Posts: 86 'Bolter | | 'Bolter Joined: Nov 2009 Posts: 86 | > edit to the original post: > Thanks Bolters for identifying the Road Tube Vent Hole for me on the block! > Please skip down a few replies now, and help me identify this vent hole of some kind > on the front driver's side of the bell housing in front of the flywheel: > http://i853.photobucket.com/albums/ab100/macx/DSCI0083.jpg> I'm new to stovebolt engines. The engine and the transmission in the '53 3100 my son and I just bought look from the outside like they have been somewhat professionally rebuilt... I'm going on the assumption that internally they are put back together and rebuilt. But the externals didnt quite get put all the way back together before I bought it... This is not the original 216 from this 53. The engine is a 1956 235. Dont know yet if the transmission is original or goes with the 56 or is something else... gonna start with the engine though. The distributer, coil, generator, wiring... All that I can handle. But there is a hole just behind and above the fuel pump... here is a picture of it... Is this for a freeze plug? http://i853.photobucket.com/albums/ab100/macx/DSCI0082.jpgThe short story on this truck: the grandson of the original owner started the restore. Got to where he needed money more than the truck and sold it to a friend. That fella worked on it some, had it for I dont know how long, but after paying rent on a storage garage and not touching it for a year he was ready to take his losses too. So my son and I picked it up, and we're gonna give it a go: http://s853.photobucket.com/albums/ab100/macx/ The body is worth what we paid for it, but I'm hoping that this rebuilt 6 is just raring to go with good compression once I get the spark and the fuel and the timing into her... But since I dont know my way around this engine yet, I dont know how to spot whats missing... After I get this hole figured out, I'll post a picture of another hole on the front of the bell housing of the transmission... that one looks like a freeze plug hole too, but its not in the engine block, so I'm confuzed...
Last edited by MacX; 11/06/2009 7:54 PM.
| | | | | Joined: Jan 2009 Posts: 14 Apprentice | | Apprentice Joined: Jan 2009 Posts: 14 | Hello MacX,
That is not a freeze plug.
That is the insertion point for a road draft tube. The draft tube vents vapors from inside the motor.
I suggest that you do not run the engine until the draft tube is installed. Oil may come gushing out.
Richard
1951 Chevy 3100
| | | | | Joined: Nov 2001 Posts: 1,519 'Bolter | | 'Bolter Joined: Nov 2001 Posts: 1,519 | Hi Mac,
Its OK to run the engine without that road draft tube. Oil wont come gushing out. Theres a baffle there to keep it from doing that.
I wouldnt drive it around like that tho. The draft tube is to vent the crankcase to below the truck,and out the rear.
| | | | | Joined: Mar 2005 Posts: 684 Shop Shark | | Shop Shark Joined: Mar 2005 Posts: 684 | The hole on the passengers side of the bell housing should have a pointer in the side of it to set the timing. There is a small ball inserted in to the flywheel that will align with the pointer. I suggest you invest in a shop manual, which will address a lot of your questions | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | http://i853.photobucket.com/albums/ab100/macx/DSCI0083.jpgDo you know if that is an automobile clutch housing? I'll check the 1956 Shop Manual and see if the timing mark (and hole in the clutch housing) is on the driver's side for truck engines. I thought the timing opening and pointer for trucks was on the passenger's side. Tim | | | | | Joined: Nov 2009 Posts: 86 'Bolter | | 'Bolter Joined: Nov 2009 Posts: 86 | In the 1955 truck shop manual, I can see a picture that shows that hole, but when I skimmed though, I didnt find any specific references to it...
... and yes, it could be a clutch housing off anything that fits... I think by the serial number on the engine that the 235 is from a truck originally... but I have'nt squirrelled around the tranny yet to find numbers to look up. The linkage to the column shifter is (I hope) hooked up wrong, because it only shifts between first and second, nowhere to go when trying to drop through neutral to get to slot for 3rd and reverse... 1 reason why they hooked the linkage back up wrong is if the tranny isnt right... But the length is right... The drive shaft is the type contained inside the covered housing between the rear end and the transmission, so the length from rear end through drive shaft, transmission, clutch housing, and engine, all fits the right mounts and doesnt crowd into the radiator... I'm assuming till I prove otherwise then, that these are more or less compatible Truck parts...
If it's the hole for the timing mark, is there not a cover or cap for it? Driving in rain or water I would think would splash water right up into the housing on the flywheel and clutch, not to mention just washing the engine off...
Last edited by MacX; 11/06/2009 9:03 PM.
| | | | | Joined: Nov 2009 Posts: 86 'Bolter | | 'Bolter Joined: Nov 2009 Posts: 86 | OK, I've skimmed through the 55 shop manual, and the 56 "tune up" manual, and I feel like a complete freshman, that's for sure... It's true, I havent held a timing light since I got out of high-school and had a job where I was able to afford a vehicle that ran without my wrenches and knuckles (1982 Honda Prelude, to a 1986 Toyota, to a 1997 GMC C/K - never needed to fix one of those myself...) so I know I've forgotten a lot in the last 27 years...
But the shop/tune up manuals for the 55/56 had the same ignition timing procedures I remember... Is this timing hole by the flyheel for determining top-dead-center, or is this for some kind of clutch/transmission timing that I'm totally ignorant about? | | | | | Joined: Nov 2005 Posts: 6,100 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 6,100 | Hy MacX, the hole for timing purposes is on the right side of the engine [distributor side], and has no cover, the hole on the left side of the engine also has no cover, and I don't know what it's for, hope that helps. | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 |
What is the engine serial number? It is pressed into the block, in the ledge just to the rear of where the distributor goes into the block.
| | | | | Joined: Nov 2009 Posts: 86 'Bolter | | 'Bolter Joined: Nov 2009 Posts: 86 | The engine serial number is: 0048730 F56Z
so its number 47730 off the line of the 1956 regular 235 from Flint.
The casting number on the engine is 3837004, which according to inliners was on 1955 to 57 Chevy 235 engines.
Looking at the 29-57 Chevrolet Master Parts & Accessories Catalog, I dont see a way from the casting or serial number to know for sure that the engine and clutch housing was originaly in a truck, but together they match the pictures in the 1956 truck shop manual.
Still going through the shop manual, though, trying to find somewhere that describes the usage of the timing hole on the clutch housing on the side with the starter...
For the hole on the other side, I guess I'll just assume its a vent, and jury-rig a press-in cap of some kind that will still vent heat or whatever, but shield water/debris from easily getting into the bell housing...
Last edited by MacX; 11/07/2009 3:02 AM.
| | | | | Joined: Jun 2005 Posts: 388 Shop Shark | | Shop Shark Joined: Jun 2005 Posts: 388 | The Master Parts Manual shows a plug (group 0.714) for the timing pointer hole. I don't see a plug for the circular hole on the driver's side. I have four bell housings in my garage; two of them have the circular hole on the driver's side and two don't. One with the mystery hole is a truck bell housing with a foot starter, and the other is from an unknown origin. The two without the circular hole are on late 261s. I don't see an illustration of the timing hole and pointer, But here is a description of the timing procedure from the 1954 shop manual. . Hoe this helps. Hoyt | | | | | Joined: Nov 2009 Posts: 86 'Bolter | | 'Bolter Joined: Nov 2009 Posts: 86 | Thanks Hoyt! Amazing how easy something is to see, once someone points out that it's right in front of you... As for the mystery hole... I'm guessing group number 0.686 in the master parts catalog ( http://chevy.oldcarmanualproject.com/1929_57chevyparts/57cmpc0149.htm ) may be the answer: COVER, Clutch and Flywheel Housing Inspection Hole | | | | | Joined: Jun 2005 Posts: 388 Shop Shark | | Shop Shark Joined: Jun 2005 Posts: 388 | MacX,
I believe that at least the first two parts in the 0.686 group are the sheet metal plate thatis attached to the upper backside of the bell housing. I'm not sure what the 3836900 p/n piece for the 54-57 Hydramatic is. I've never had the opportunity ot look at one that closely.
Hoyt | | |
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