some jensen 75 measurments

Rob · some jensen 75 measurments

please could someone with a jensen 75 tell me some measurments of the cylinder and connecting rod and eccentric rod. would like to know the length of the whole thing when fully extended. trying to see if one will fit on my engine.

after watching mr o's vids on youtube, i noticed the reversing lever moves a lot. what happens if you hold it in a fixed possition so it doesnt move?

if there are any pics which could accompany the measurments they would be very much appreciated, especially of the reversing gear.

cheers

johnreid

Give me a chance to make some measurements, but a 25 and 75 are the same

will make some measurements and post later.

johnreid

Allow me till it is daylight here in the US and I will take a few pictures with a Metric rule along side the Valve gear. It is 6:54 PM here and dark, the flash makes the markings on the tape not show.

redryder

If the 25/75 eccentric rods are too long, I believe the #20 linkage is a hair shorter, perhaps by near 1/8 inch.

Gil

Mister Occlusion

Don't have any measurements for you offhand, but I can tell you this.

If you were to hold the reversing lever in place at the end of its travel, while the engine is running, to stop it bobbing up and down (that was your question, right?) it will drag the engine to a halt, or very nearly so.

However, you can do this. If the engine is running with the lever down, you can lift it up to where it is at the top of its "bob" and hold it there and the engine will continue to run. You will lose a few revs, but it works. If you hold the lever thus and continue to lift it the engine will slow further and when you reach the neutral area in the centre it will stop entirely.

It's an interesting way to control the speed.

If size is an issue, the Model 65 is smaller. It lacks the valve gear, though, and uses (I believe) a slip eccentric.

I should be getting my used one in the mail next week some time, and then I can actually make a few *educated* guesses

Rob

thanks very much for the advice and info already.

johnreid

hope this is good enough

Rob

yeh big help, thanks john.