MikeScarab28XLT

I have ask Rinda:
if i drive what shows me the program? The programed table ore the table +8* base time.

If i see 29,53* in diacom at 3200 rpm.

Are the 8* base includet ore not.

What total i have if i see 29,53* in diacom?

29,53 + 8 = 37,53 to high
29,53 - 8 = 21,53. To low

anwser:
You would have to ask MerCruiser, we simply display the timing data that the ECM reports to us.

MerCruiser sets up all of the ECM data tables and software.

We don't have any engines here, we are software developers strictly working on the diagnostic tools.



cut the case down

Mbam

I do not trust the timing lights that are supposed to measure the advance. After testing every one on the S*** - *N truck with my distributor machine could we not find one that did not have at least 3 deg error. I will admit this was a long time ago and they might be better today. I do not trust them even when set to 0.

Nothing beats a degreed balancer.

The ECU and the data shown on your scan tool have no idea what the base timing is. As you know there is no crank position sensor like on the new engines. So yes - the total timing is going to be the reading shown + the base.

If not locked in base timing mode it will move all over the place and 30 degrees (plus whatever the base is) at part throttle with some vacuum in the manifold would not surprise me at all.

If you have an 8" balancer it is easy to put a 36 degree mark on it, that works out to be 2.513 inches. Which makes 2.5 inches just a fraction off. Use a flexible machinists scale and put a mark at 2.5 inches to the right of your 0 mark. At least you will have a reference you can count on. And coincidently that is where all the stuff we used to build liked to run at.

You did check your TDC mark and pointer to make sure it's TDC, yes?

MikeScarab28XLT

Thank you Mbam for your help.



I have changed the MArkV Block to MarkVi and now i have a Timing gain cover with only one pin. Hope it is 0 and the old balancer.

i have rotate all Spark plug wires on the distributor Cap, becouse i had no room to rotate the distributor (oelcooler, Ram, VST,)
Is it important that the marking 1 on the distributor cap are the wire 1 ? Ore can i rotate all spark plug wires 1 pin.



If i put a marker on the balancer with the making 32*,can i rotate the distributor at 4000 RPM and timing light at 0 advance that the light point to the 32* marking. Than i can double check it with 32* advance on the timing light and the light point to 0* on the balancer.

MikeScarab28XLT

I have buy 2x tapes from Mr. Gasket #1591. Chevy 8" Dia.

I go testing.

Mbam

Yes, you can move the wires anyplace you want. My preference is to keep them in agreement with the numbers on the cap, makes life easier down the road. Pull the distributor and move it a tooth.

I would allso get a pison stop, the kind that goes in the spark plug hole. Pull all the plugs and check TDC. I can't remember if the valves will hit the stop, best to pull the rockers unless someone here knows for sure. You should be able to find instructions online someplace how to use the stop. I am too poor a typist to do it here !

MikeScarab28XLT

My new cap have no marks, numbers on it.
OK tape flay away in some seconds. I used the tape to mark the balancer with a white pen.

Now i have make a base time to 10*.

Now i have test it and the diacom sows me 30* not the 29* last i have see???????
But it shows me 30 including the base of 8. Real light i have the 32* on the markings. So i have to add +2 to rinda. 8+2.

If rinda show me 30 i have 32 real total. 28 with rinda i have real 30 total. Now im more happy to now it.






this is not running engine

fireguy

deleted

Carbon Footprint

iTrader: (4)

since this thread seems to have gotten hijacked, I need some help on the original topic of my surging idle and wanting to die.

Just ran the boat on the hose, put a fuel pressure guage on it and found something interesting..... I also checked the manifold for any leaks by spraying carb cleaner at all gasket areas and no leaks were found. My static and running fuel pressure are at 30psi. when I bump the throttle to 1000 or 1200 and get my surging, the fuel pressure also surges from 30psi down to about 27 psi in sync with the pulsing of the engine.
This is a VST 502 all stock except for cmi etops. Have already replaced IAC, checked MAP sensor, and no changes. this seems like perhaps a fuel pump issue???????
Also code scanned and no codes found.

MikeScarab28XLT

Hello high&Dry,

i have the 1993 engine, the only i have read are allways 37-39 PSI on FuelRail. I have buy some new Pressureregulators original from Mercruiser and the make allways 32PSI without vaccum, with are 27PSI. The pusling i have too. I have than canches bots mechanical Fuel Pumps, same pulsing in fuel pressure.

I have test adustabel fuel Pressure regulator. I put the fuel pressure to 39 PSI, 40PSI and 45 PSI no diffrence. At 45PSI the boat are slower, so much fuel :-)

I have buy the EFI Upgreat Kit with ECM reprogramm and the have say to me go from 39PSI to 45PSI. But the engines not run. I go to 32PSI and the new programm works. But slower than may stock ECMs. Im happy becouse i have 4 ECMs. 2 Original and 2 reprogrammed.