454XL fuel pump

"Mako, how much shorter than t

"Mako, how much shorter than the 5.76" can the push rod be before I should replace it?

My fuel pump is an AC not a Carter - does that make a difference re the sight tube? If the AC pump should have one, mine don't. I can't find anything that tells me about installing the AC pumps so I don't know if this sight tube has been removed or was never there to start with."

The sight tube is what makes t

The sight tube is what makes the difference between an automotive fuel pump and a marine fuel pump. If you have an internal leak on an auto the fuel comes out a vent hole on the side of the pump and drips on the ground. In a boat that fuel would be trapped in the bilge and become an explosion hazard. On a marine pump there is a small tube where the vent would be. You slide clear tubing on the tube and run it up to the carb where it attaches near the top. It enters the carb above the throttle blade where there is no vacum. The tube allows you to see a leak and dumps inside the carb for safety.

"I'd think if it shorter

"I'd think if it shorter than spec, there are two possibilities. 1) your measuring instrument has an error or 2) the rod is worn. On the first topic, I'd suggest you check the instruments manual to see how much error it may have. If the rod is worn, I'd be sure to check the cam eccentric tto make sure it is serviceable before putting it all together. If the rod and the eccentric are both worn, this will reduce the pump stroke which meaans less volume and maybe less pressure, too.

A new rod should be less than $15 from an autoparts store. You could just replaace it but check that cam first. If it's worn, probably time for a new top end.

the sight tube connection should be there. it should be a little hose barb <= 1/4". See if there is a pipe plug in the housing, betwween the two diaphrams, probably facing aft. If there is, that's where thte tube should connect. Here's one on ebay:
http://cgi.ebay.com/ebaymotors/CHRIS-CRAFT-OWENS-US-MARINE-FUEL-PUMP-283-350-409 -NEW_W0QQcmdZViewItemQQitemZ250365899089

if you look under the pump's rocker arm where the push rod would contact, you can see the pipe fitting - that's where the sight tube should connect.

I'd say if the rod is less than 5.75 (10/1000 ths) its timme for another one. you could also get a machinist's opinion."

"Thank you for your advice gen

"Thank you for your advice gentlemen, much appreciated.

I'll check the push rod tonight and see what it measures. Will it just slide out through the plug hole or will it need a tool of some sort.

I've had a look at my carbs and I don't see any sign of a nipple or vent that would accommodate a plastic tube to the fuel pump (I can't even tell you what make my carbs are). On the fuel pump there is only a hex key plug on the plate that's between the pump's diaphragms. Neither of my engines have a sight tube so I wonder if it's newer technology than the 1985 Crusaders I have - no worries, I don't go very far or fast in my boat so the explosion should be easy to see from shore.

Over."

"Peter;

once the plug is ou

"Peter;

once the plug is out, the push rod slides out. The exception is if there is a lot of gum/varnish on the cam side of the bore. If the pump is out and it slides down to the lug, this shouldn't be an issue.

You can ID tthe carb visually. The factory put quadrajets on them. This should be readily visible on the side of the bowl, usually as "quadrajet by rochester" in two lines. If that hasn't changed, the sight tube fitting should screw into the front of the float bowl, about the fuel line fittings. If not hose barb sticking out, look for the tapped fitting. there should also be a set of numbers, along the back of thte float bowl, starting with 1705xxxx, most likely. (You can probably find good pic by search ebay.)"