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Engine won't START - Need some help

P

ptudozer

Member
MerCruiser 5.0 MPI
Just installed new Cylinder heads, and performed a valve lashing according to the manual.
Placed #1 cylinder on TDC -- Verified with mark on balancer and that both valves were closed. Installed the distributor with rotor pointing to #1 firing position. After installing the intake manifold, I did a cold compression test -- results 140-145 PSI per cylinder
I can verify that there's fuel in the fuel rail. although I don't have a gauge to check the pressure
Pulled #1 Spark, was wet with fuel, but not too bad. Scope camera did not see any fuel pooling on top of piston
Spark plugs are new
While #1 Spark plug was out, I was able to verify a blue spark when cranking the engine.
All sensors are plugged in -- at least the ones I disconnected to remove the heads.
Computer is plugged in

Any advice on what to check? It's a twin engine so I can always pull parts from the other to test

Thank you
 
I'm pretty sure you have the 555 ecu with the HVS distributor....they aren't 'normal' in terms of phasing the crankshaft and the distributor....in other words, you don't set the timing by moving the distributor. the HVS position is very critical and the engine likely will not run without following the procedure to set the distributor...

there is a procedure but I don't have my manuals handy...you can do some web searching or maybe somebody else can post you the details...
 
if you have the HVS type you drop the dist in with the rotor facing the mark after getting #1 to TDC compression
 

Need Help Installing Distributor in 4.3MPI

I'm to the point of installing the distributor in my brand-new 4.3 MPI engine. I have the engine at TDC on the #1 cylinder, ready for it to be installed. According to the manual, shown below, I aligned the tang of the rotor between the two marks. Between these two marks on the distributor is a...
forums.iboats.com forums.iboats.com
 
If you click on BT dosctors link, then read the forum thread it should answer your questions. Of course he references HVS type system.

If that is what you have, there is a casting mark on the dist housing. You align to that mark. For the V8 is says there is an 8.

From what i read the dist cap is the clam shell type (spark plug wires attach sideways) so when you align rotor to mark it aligns to the proper dist spark plug wire location.

If you have a round dist cap with the wires attaching to the top of the cap, that may be a different ign system
 
Bt Doctur
Ok I think I got the correct information...it's already too late and I'm frustrated with this engine, so I will TRY to get some sleep and start over in the morning.
So, since my engine is a V8 which I now understand, uses the same Distributer (not same cap) as the 4.3 V-6 engine.
I will have to make sure the rotor is aligned with the "8 mark" on the distributor which should be just past the #1-cylinder firing position on the distributor cap.
If I don't have the correct information, please point me in the right direction
Bt Doctur said:
if you have the HVS type you drop the dist in with the rotor facing the mark after getting #1 to TDC compression
Click to expand...
Man, I forgotten how exact you have to be with the setting of the rotor. If it's not on the mark exactly, she will NOT start.
I did this 6 years ago when I re-installed the heads...
Thank you for all the info, I was getting upset at this engine.
Just got ut to fire up, now time to hook it to the hose and make sure all checks out before taking her out for a nice run/shakedown đź‘Ť
 
makomark said:
I'm pretty sure you have the 555 ecu with the HVS distributor....t
Click to expand...
Bt Doctur said:
if you have the HVS type you drop the dist in with the rotor facing the mark after getting #1 to TDC compression
Click to expand...
kghost said:
If you click on BT dosctors ...
Click to expand...
Just wanted to say thank you all for the help. So, turns out I was pretty close on the setting of the distributer, but not good enough....LOL
Also, somehow while putting the new heads on and working on the motor, the raw water pump/impellor got reversed, (no clue how) and because it was dry, it would not correct itself when I cracked the engine and was making the belt slip... I guess that resistance did not help things. I was able to then get the engine started fine without the belt. After getting the impellor corrected, the motor starts fine and runs PERFECT.
Took her out this weekend, and I couldn't be happier. performed very nice, and I think the performance increase just a small amount (maybe it's all in my head). Temperature stayed 156-160, oil pressure 45-60 PSI and coolant (raw water) pressure 10-12 PSI
This forum has been a tremendous help.
 
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