Rotunda timing meter - pulse clamp

[rockbender]

I recently picked up a Rotunda timing meter that is set up with both a lumi probe and pulse clamp. What I didn't research before my purchase was that the clamp is specially made to fit 7.3 injection line sets (#1 on trucks, #4 on vans evidently). Has anyone used a different line clamp with these meters? I'd really like to time via pulse method if possible. If this isn't feasible, I may opt to sell this one and let a 7.3 owner take advantage of its functionality.

I am missing the cetane checking device, so I'd be unable to really dial things in via the lumi probe but I suppose it is better than nothing!

 

[riotwarrior]

So what you are saying is it WON"T fit you injection lines? Have you tried it?

Just gotta ask right...

Al

 

[rockbender]

Yep - no question is a silly question! I have not tried, but the clamp is probably in the 1/2" - 5/8" diameter range and it seems that the 7.3 injection line on #1 has a groove made for this clamp. I will double check tonight to be sure... but it looks closer to fitting the injection line nut than the line itself.

 

[cpdenton]

I think that clamp must be for use on the 7.3 factory timing adapter that is between the injection line and the injector. You could always swap that line out for a 7.3 line and adapter.

 

[icanfixall]

I think that clamp must be for use on the 7.3 factory timing adapter that is between the injection line and the injector. You could always swap that line out for a 7.3 line and adapter.

This is exactly where that line clamp fits. Remove the plastic cover it usually has on it. Then apply the brass clamp to the fitting between the injecter and the line. Then you can time using the clamp pulse method like you want too.

 

[rockbender]

This is exactly where that line clamp fits. Remove the plastic cover it usually has on it. Then apply the brass clamp to the fitting between the injecter and the line. Then you can time using the clamp pulse method like you want too.

Yep - I'd be all over this if I had a 7.3 or 7.3 injector line set! This is exactly the clamp you guys are talking about. However, since I have a 6.9 I was wondering if I could use a Snap On or similar clamp that goes on the injector line with the Rotunda meter and pulse adapter box (or adapt the existing clamp to work on the line).

 

[icanfixall]

Yep - I'd be all over this if I had a 7.3 or 7.3 injector line set! This is exactly the clamp you guys are talking about. However, since I have a 6.9 I was wondering if I could use a Snap On or similar clamp that goes on the injector line with the Rotunda meter and pulse adapter box (or adapt the existing clamp to work on the line).

This may work but why buy those parts. The van engines time off the number 4 cylinder because they have such bad access to the number one cylinder. All you need is the hard line timing adapter found on any 7.3 engine and that shorter #4 hard line. Acurate Diesel sells new van or pickup truck hard lines. Might even sell the adapter too but not sure.

 

[rockbender]

I think I'll start by checking via the lumi method to see if I'm in the ballpark or not... I can always run a little on the conservative side without knowing my cetane value. In the meantime, keeping an eye out for a #4 van 7.3 line and adapter would certainly be a good option. IDIDieselJohn... you have one of these kicking around there, van buddy? It sure would have been nice to do that work BEFORE installing my AC compressor!

 

[icanfixall]

Any timing adapter will work on any idi engine so don't feel you can only use a 6.9 on a 6.9 or 7.3 on a 7.3. They are the same adapter. Just the lines are differant lengths. Never try to force a short line to make up the missing adapter. That shortens that line and the cylinder is way more advanced than the other 7. Notice on top of every intake port runner near the heads is the number of that cylinder cast into the manifold. Sometimes they have road dirt covering them so clean it off. Drivers side is 2-4-6-8 at the firewall. Passenger side is 1-3-5-7 at the firewall.

 

[rockbender]

Thanks for that info, Gary. So if my research is correct, the 7.3 line sets are .060" shorter due to the injectors being shallower in the head by the same amount. However, if I change out just my #4 line to a E-series 7.3 line with timing adapter then that change in length should be negligible to timing, correct? In theory, that #4 line would be ever so slightly advanced compared to the rest of the lines that would be stock 6.9 lines.

Remember, this is a van. With a turbo and AC. I may still be better off to sell this meter and rent or buy a Kent Moore! I'm hoping to have some time this weekend to dive in and check things out. Thanks guys!

 

[icanfixall]

The differance in the 60 thous shorter lines is not an issue. These engines are not a NASCAR engine built in an operating room. What I mean by not stretching a line to fit is don't do this on the line with the adapter on it if your missing that adapter. Some members here have actually bought rigs that some idiot has bent a line from another cylinder to fit what they wanted. Thats the wrong thing to do. Only one good reason to do that and thats to get home safely. But change it when you get home. Any injecter line your trying to fit to any cylinder injecter can be "moved" enough to fit nicely. I always thand thread the lines to the injecter all the way down. Never start them and use a wrench the rest of the way. I stripped number 7 injecter once and what a hell of a mess that was. Luskily the line nut is hardened material and the injecter is soft. So the injecter body was replaced and thats how I fixed that mistake. Its really easy to bent a line to fit an injecter. If its not threading on correctly just use the box end of the 5/8 wrench on the line up past the nut to "incourage" the line to fit. Then hand tighten it. Once thats done you wont ever have a issue there again. Or in the worst of cases loosen the injecter line at the pump too. Then hand thread the line at the injecter. Its usually much easier doing this but the bottom 4 lines are tuff to loosen without the special wrench made for that.