New to me 175 OMC fuel problems

[gotboostedvr6]

I have a 85 VRO 175 Crossflow on my Proline W/A.

The first time i started it the thermostats were both clogged so i removed them. I have replacements on the way. Temp problem fixed.

Next problem was it just idled like **** and had no power. I then pulled the carbs and did a through cleaning.

Stared it again ran alot better idled fair-good with a lioght sneeze every 10 sec or so. The bowls stayed full of fuel.

i took the boat out and got it on plane it ran like a raped ape for 10 sec or so then started dieing... I checked the primer bulb and it was still hard.

i took the boat out again and cleaned the carbs again.

I dipped the boat in the water but left it on the trailer so i could do some load testing. It would only make it to 3400 rpms or so 15-20 sec before it fell on its face and shut off. I checked the primer bulb and it took 4-7 pumps before the bowls were full again.

So I'm now thinking the vro/ fuel pump is bad but its intermittent because this doesn't happen every time.

Sometimes when it starts dieing on plane, 25 mph 4k rpm, I can push in the key choke and the motor will bring itself back to life.

All signs show fuel starvation.

Another thing to note Im using a brand new run of the mill 6 gal portable fuel tank and new 5/8" omc fuel line could this be the issue? Maybe the fuel port on the tank is too small and is a choke point.

[gotboostedvr6]

So far I've rebuilt the carbs, replaced the vro pump Found a bad coil and replaced it ..... so far it seems that the fuel problems fixed, motor runs like champ but only for about 2 min till it starts to slow down.... fuel bulb stays firm.

I think i might have a bad power pack what do you all think?

It slows down for 12 -13 sec than picks back up idles fine

[Tomtall]

First off when you say it slows down does it do it sloooooowly or like a light switch being turned on. Sloooooooowly is usally fuel starvation. On and off quickly is usally ignition. If you have a timming light, have someone drive the boat and check to see if all your cylinders have spark when the problem occurs. Do one plug wire at a time as the lack of rpm happens. If you find a cylinder with no strob on the light then you have found you dead hole. Also never assume your new tank and hose are good. Find another known good tank from a friends boat and try it. I just got back from the shop where the guys had been chasing a similar problem all week with a merc 115. They swore it was droping a cylinder after it got up on plane. After ten minutes out on the lake I found the fuel filter had a piece of rubber blocking off 3/4 of the outgoing end. A $6 filter fixed the problem. Remember it's sometime the small things that bit you.

[whaledog]

Check fuel starvation ,restriction in fuel pickup.use clear vinyl hose to check for air leaks(bubbles in fuel supply line)install fuel line T and install vacume gauge.run engine full throttle with test prop or in lake run.fuel vacume should not go over 4 1/2 inches vacume.then check fuel pressure after vro pump should be 7 pounds.pressure checks can be made on the vro itself with vacume and pressure testers outlined in service manuals.check kencook publishing for manuals.

[gotboostedvr6]

The first cut or slow down is abrupt. it goes from 5500 rpm down to 4600 or so than down to 3300. The fuel bulb stays firm never softens up

Ill slow to craw for 15 to 20 sec then run it back up to 40mph and the process repeats itself