Flyer5
Well-Known Member
- Dec 2, 2022
- 2,058
- Boat Info
- 1987 Sea Ray 410 AC
1987 Sea Ray 268
- Engines
- 454 Crusaders
Hi Duck! I wasn't challenging your conclusions, i was just bringing a point of information, as I had a different, but related scenario that enlightement of the fact would have saved me some heartache... the circumstance being that most don't realize that the FP pushrods are not all same size... and to complicate worse, the fuel pumps aren't same either.
On subject of fuel pumps... USUALLY the separator filter is BEFORE the pump, not after.
I don't think the filter separator would be under any great stress of subjected to a few psi of downstream pressure, but they're fitted with the filter's seal. If i we're the engineer designing it, i would have made it capable of safely withstanding both positive and negative, but I wasn't that guy.
As others noted above, the anti-siphon valve at tank is a minimum-pressure check valve... it's cracking pressure isn't much, but it is enough so that some pumps might not prime effectively... so if you have challenging results, don't let that scenario foil you.
Just stick a flat screw driver at the end of the rod and pry the rod towards the camshaft have someone bump or crank the engine. See how much it moves. Doesn't need much.
The lobe wear-pushrod length just doesn't seem right to me. Loosing 50 thou of that rod isn't a nightmare, but to lose enough lobe lift to cashew your fuel flow, means the hardened cam surface has been cut through.
I'm very good at destroying things, and I've flattened a whole row of valve lobes, but I've never worn through a fuel pump lobe on a camshaft... and this is why it just doesn't seem right. if it were me (and it is a genuine pita to do in most boats) I'd cut apart a junk fuel pump, fit the body onto the block with rod in place, and measure the actual lobe lift with a dial test indicator. If it really IS a flattened lobe, then the next concern, is the other 16 lobes on that camshaft, that are under significantly more severe duty than that fuel pump... they might be very close behind.