TR6 TR6/250 water pumps and a dumb PO [me]

[TR6oldtimer]

Some time back I put a TR250 engine into my '73 to replace the tired original with the intent of rebuilding the six engine later. Well that engine was to expensive to rebuild, so I did the 250 which is now done. Apparently, some time in the past I replaced the 250 water pump, with a narrow pulley water pump for a TR6. After all the work getting the engine fresh, and everything back on, it was not until I went to put the fan belt on that I noticed it was the wrong pump. Now I know I had the old pump, so I looked everywhere for it. I did find a second pump for the six. In my mind, I remember I saw the 250 pump, but for the life of me, I cannot find it now.

I asked myself, "Self, did you really have a 250 pump?" So I looked at the pictures before I ripped everything apart, and low and behold, there on the engine was that TR6 pump, with the belt riding high, dah, what an idiot I was. Drat, that means I swapped the pump 15 years ago. Still, I thought I saw it just a couple of years ago.

<span style="font-weight: bold">But WAIT, the 250 had the narrow pulley</span>, the '73 had the wide pulley, yet the alternator and crankshaft pulley on the 250 engine are wide. So it appears, when I did the 250 engine swap years ago, I used the damper pulley off the six to match the wide pulley on the alternator, but installed a 250 water pump.

Low and behold, there on the six engine is the narrow damper pulley that should have been on the 250. (which explains why my six had no timing marks, yet the 250 did).

Oh, I also found out that the narrow damper pulley is about 3/4 of an inch less in diameter then the six, which means the water pump and alternator would have spun slower on the 250 then on the six.

So, what to do? Buy a wide pulley water pump and get on with life, or buy a narrow pulley for the alternator and use the smaller 250 damper pulley?

I know the answer, buy the wide pulley water pump. But then again...

So, how is the quality of the water pumps now being peddled, and are the wide pulley pumps only available with the ugly double pulleys?

Getting old is tiresome.

 

[DNK]

RAY, hope not too may more post like that. I needed a flow chart to keep track

 

[TR6oldtimer]

Don, yes, way to much coffee this morning.

 

[tomgt6]

What does your gut tell you to do? Then listen to your wife. I would say get the right stuff so you don't have to remember what you did. If it is a 250 engine then get the stuff for a 250. Keep it simple in the long run.

If you ever sold the car you could say it is a tr6 with a rebuilt 250 engine and then the new owner can buy the parts correctly.

 

[TR3driver]

Just a thought, Ray, perhaps there was a reason they went to that wider belt? It seems an odd thing to change, unless there was a specific problem being addressed.