I just bought a remanufactured 351M for my 78 F-150. Unfortunately I dropped off the old one before the new one came in. I don't remember where the temperature sender goes, but I'm sure it was on the front of the engine and not on the intake. It will fit (thread size) into the intake in two places, but I know both of those places get vacuum fittings instead. No other place near a water passage seems to be available near the front of the engine.

Also, my old engine had the base of the dipstick coming out of the driver side of the oil pan. The new engine I got has a hole drilled on the passenger side of the block near timing cover (I assume for the dipstick) but it is not threaded for a cap fitting. What do I need to block off that hole?

 

the temp sending unit does go in the front of the block.It is located on the right side about 2" below the thermostat housing next to the water pump.Actually its close to that open dipstick hole you are talking about.

I dont know where you can get one but ford drove a tiny,what looks like a frost plug into this hole.You could also tap it and install a pipe plug.There is no oil "pressure" here so you may also get by just sealing it with RTV silicone

 

I recently swaped my my '79 Bronco's old tired 400 with a freshly rebuild one from a 2wd truck. Ran into the dipstick problem you mentioned. I pluged the "block" hole with a 3/8" expansion plug. Like mentioned earlier, looks like what Ford used from teh factory. Hasent leaked once in 4000 miles.

Now to work on htat leaky power stearing system......

 

I elected to use the block hole for my dipstick because I didn't like the dipstick sleeve into the oil pan design. Seems i dont have the right length dipstick now. I think i need a dipstick from a mercury Cougar w/351m.

 

Well, I just sold one of these (a 351M) the other day.

From our sources at work, there are 2 versions:

you can buy a block that has a dip stick hole in the block, and another that doesn't (in the pan)...Just so you guys know.

Matt

 

Phil , is your truck a 4X4 ? If so you will have to use the oil pan mounted dipstick tube hole to get a correct dipstick reading. The 4X4's use the rear sump oil pan which needs the dipstick at the rear of the engine, the 4X2 use a front sump pan, thats why the dipstick tube is on the front of the motor. As far as plugging the front hole you can use a small freeze plug ( that 3/8" mentioned above seems right, but its been awhile since I did this. ) put a little sealant around the plug and tap it in the hole, it dosen't take much to get it in there.