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Crusader 454XL-TB Starting/running problem

Captfredsr

New member
I have twin 1996 454XL-TB Crusaders with approx. 1800 hours. Tune-ups, oil, filters are on a regular schedule. Problem: Starboard engine when up to running temperature, will start, then the RPM's will fall off till it stalls and will do that several times without idling. Sometimes after several tries, it will say running. Nothing shows out of spec on the computer and mechanical vacuum read 15 inch steady when idling at 650-670 RPM. Timing set 10 BTDC, gas pump pressure is 20 LBS running and it operates upon start with 2 second prime. I can hard throttle it with excellent response. After starting cold, it runs great, it preforms excellent through all RPM ranges on the water. What I have done to correct,(all parts are Crusader purchased) replaced: Knock sensor, Gas pump Relay, Starter solenoid, Temperature sensor, MAB module and vacuum hose, distributor Mag pickup and Ignition Module, used two new electric gas pumps, gas filter base and shutoff valve, gas main supply line to tank, fresh gas 90 gallons, switched to generator gas pickup port on tank and returned to engine port, swapped TB units and ECM from port engine that ran good and no change with swapping these units. So I'm stomped. My wife and I are 71, so we need this engine to be trustworthy. We do a lot of on water local anchoring in the Barnegat bay. Local marine mechanics are impossible to get available and I did try!! Any suggestions would be appreciated.
 
is the fuel pressure steady when the issue occurs - the ECU doesn't monitor it - ?

Have you checked the cap and rotor to ensure they are in good shape?

may also try swapping the ignition coils as it sounds like most other likely subjects have be swapped between engines or renewed...

also, please clarify (operating conditions) when your issue occurs...I'm thinking after warmed up and running for a while, then Stbd engine RPMs fall off and eventual engine stalls...
 
is the fuel pressure steady when the issue occurs - the ECU doesn't monitor it - ?

Have you checked the cap and rotor to ensure they are in good shape?

may also try swapping the ignition coils as it sounds like most other likely subjects have be swapped between engines or renewed...

also, please clarify (operating conditions) when your issue occurs...I'm thinking after warmed up and running for a while, then Stbd engine RPMs fall off and eventual engine stalls...
n

The cap, rotor, plugs and plug wires in good condition replaced 2 years ago. Ignition coil is new (missed that earlier). Sea trails are excellent in all sea conditions, engine maintains any set RPM which I change anywhere from 2200 to 3200 (cruse RPM) to as high of 3800 and we stay on water for at least 1 hour or more. Coming into the marina requires idle for 12-15 minutes with stable RPM. Once in the slip, it will idle as long as needed, doesn't stall and RPM is stable. Once turned off for a short time, then I have the problem with restart. I have noticed unstable fuel pressure during restart but doesn't drop below 14 pounds and maintains 20 pounds when running. That's why I stated two new fuel pumps thinking the first one was defective. Also note running temperature has been verified normal and oil pressure excellent at all RPM ranges. Also checked for anti-siphon valve which I didn't find in fuel system. All fitting in good condition. ECU computer data only shows fuel rate, not pressure. I use a remote fuel pressure test gauge for pressure reading, Thanks for trying to help, I'm
at a loss!
 
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The fuel flow is a calculated value, not measured, so take it with a grain.

What you described this time around is a hard restart once warm, with a short soak time....

On the anti-syphon valves, they look just like hose barbs...Unless your hull is ancient or off-brand, I'd bet they are on top of the tank. That said, I can't say I've ever seen them cause what you are describing.

can you open the hatch once you shut off the engine? do you 'cool' the engine before you shut it off (fast idle, in N, and let the blower(s) run)?

How long has this been happening?
 
15 inches of vacuum seems a little low to me.Check for vacuum leaks.If none are found try advancing the throttle slightly when it wont stay running and see if that helps.If it does check your tps setting and base idle.
 
15 inches of vacuum seems a little low to me.Check for vacuum leaks.If none are found try advancing the throttle slightly when it wont stay running and see if that helps.If it does check your tps setting and base idle.

I'll recheck for vacuum leaks. TB gasket is new due to the switching it from the port engine. May need to pull of intake manifold to take a chance on a gasket problem that may be internal. I have tried slightly advancing the throttle but RPM still continues to drop off. TPS volt values are in range, QUESTION: how to check base idle? Maybe by disconnecting ECU connected to the TPS?
 
Reference "flow rate" Something I would have to test for hopefully without installing a Flow Meter" It can sit for a week and start multiple times without an issue. I removed all fitting which are threaded up to the elbow at the tank, ran thin plastic line through till I hit fuel, so no Anti-syphon valve. My fuel line engine to tank is Aeroquip #6 w/ screw on fittings (all new) no barb fitting. Temperature without load raises normally to about 160-165 deg. and still starts most of the time, once underway temperature stays around 170-175, the problem comes back yet temperature remains 160-165. Yes, I turn on the bilge blowers as soon as I start my cool-down run bringing the RPM's down slowly from higher RPM's or/and anytime I am at an idle coming into the dock or maneuvering. Blowers stay on for about 20-30 minutes once the engines are shut down. I can open the hatch if needed but the couch is hinged above it, so I normally close it anytime underway for safety. Could reinforced it if necessary to keep it open. How long? Problem started July 5 this year, yet ran fine till then. We launched it March 15 from winter haul out. I won't forget that date because that's how long I been fighting this problem. We've owned the boat since 2009 without any engine problems just normal maintenance.
 
If it still stalls when starting hot with the throttle advanced its probably not a base idle adjustment.You can check it if you want just google gm tbi idle adjustment its the same system that is on gm trucks.Compare the vacuum reading on good engine to see if it is also the same before taking anything apart.That WOT also seems low to me.Are you sure you have a good base engine might be time to do a cylinder power balance and compression check.You can also compare fuel presure readings to the good engine.If your not testing fuel pressure when the problem occurs then the test is meaning less.
 
Thanks, I agree doesn't sound like a base idle issue but still may look into it. When it stalls, it's a slow RPM drop from idle which would make me believe it's a fuel problem. I compared the computer readings from both engines by charting each sensor side by side. All readings are so close to each other so I don't see a problem. Vacuum remains at 14.7-15 as I am told is a little low. I need to check / replace the gasket adaptor to intake just to be safe. I'll take a look again comparing the vacuum readings between the engines with a test gauge. I don't remember a big difference but well worth re-checking. Start / running fuel pressure similar between the engines but the problem engine is a bit erratic at times at hot start. I know that's not good. Could air in the fuel system be a cause although I have no clue where it could be coming from with all the new parts and switching TB and ECU from the other engine. Keep in mind the port engine continues to run great even with the changing out.
 
I agree it is starting to sound like a fuel issue assuming the engine is mechanically sound.Dont think you should throw any more parts at it until you have more clues on which direction to go.It is possible its sucking air in the fuel system but would have to be before the pump other wise it would be a fuel leak because everything after the pump is pressurized. Maybe a vapor lock issue but without the other engine doing it I doubt it.Something you can try is when problem occurs is pump the throttle and see if you can keep it running and eventually get it to idle.The reason I say that is because the TBI system is programmed to add a extra squirt of fuel each time the throttle is advanced quickly when running to act just like a accelerator pump.If you can keep it running by doing this and can get it to eventually idle I would definitely say its a fuel delivery problem.You can also try turning the ignition on and off several times and pausing 10 to 15 seconds between each cycle when problem occurs to activate fuel pump several times to purge fuel system and build pressure and see if that effects problem.
 
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Throttle idea, never tried the quick pump just a slight advance. Interesting thought! I have tried the key on-off before with little success on start. For me the next thought doesn't make sense but I'll throw it out anyway. Even though it sits for a week, starts and runs great for hours at all RPM, any chance I have a tank "pick-up" tube issue causing the possible air prior to the pump?
 
Any thing is possible at this point.Can you leave the fuel presure gage on the engine to see what it reads when problem is acting up.If you did have an air leak I would suspect it be at the tank selection valve as that has moving parts and seals that may be effected by heat.The key to finding your next step is when problem is acting up are you loosing fuel or spark.
 
Yes, I've exhausted everything I felt or found to be under spec. The first time it wouldn't start and found no fuel pressure, the first new pump and tank supply line was replaced which was suspect of being the problem. After than it's been piece by piece replacement or checking of associated parts which could be a caused the problem including the parts swap with the sister engine. We have also vacuumed check with test gauge and along with pressure gauges, use of the computer engine data hunting for the problem. Each part replaced was then sea trailed to test our theory. I did lose the spark one time; the distributor mag pick-up had failed. I believe it was from testing the fuel pump and system and not starting the engine caused it to overheat. I would think if it was a heat related electric or spark issue the engine would give an indication of a problem during a long sea trail. It just runs excellent! To pull the tank pickup tube will require some cutting of the floor and interior wall. Just haven't found anything that could be a problem externally, but may not have any choice. I neglected to add the fact, always had at least 1/4 tank of gas but did fill to over 3/4 (I can use a stick into this side fill to verify) without any engine change. I will try everyone's suggestion! But it's due to be pulled for the winter, so it's going to be a long winter with this problem driving me crazy! And just think, haven't had a problem with the port engine, which may be next! (Hope not!) I really appreciate all the help I been given and hope I can help someone else on the forum. Please keep your thoughts coming, for everything must be will be looked at to resolve this problem so I can get the reliability back in this engine next season!
 
If your loosing fuel pressure don't overlook the electrical side.I have seen many relays and connections act up at certain temps and I always carry a couple spare relays.It would be very easy to hook up a indicator light to see if your loosing power to fuel pump which it sounds like you are if you had zero fuel pressure when it happend.If it is a relay I would suggest getting the number off the relay and only get an ac delco also the same ones on the truck tbi systems.The china electrical components rarely work very long and cause other problems.
 
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I've replaced the relays from a Crusader dealer, but I didn't take notice if it was an AC Delco. Could have been re-packaged, that's a good question I need to verify. A wired-in indicator light is a great idea. Thanks! Relay problems! Four years ago, my port engine began to "break-up and wouldn't go over about 2800 RRPM. Long story short, my son has a multi-meter with a digital screen for graphing. Went out for sea trail with it and the computer hooked up, after several runs, he had me stop and shut-down. Found the meter display graphed erratic voltages from 14.5 to 6 volts which caused the computer RPM to show over 2800 to 8,000 RPM. So, the ECU was reading "Over RPM" and cutting the ignition to "protect the engine" although RPM was only 2800 or less. Answer: "chattering ignition relay!! Replaced it and it resolved the RPM problem. Never would have found it without that specialized meter other than replacing a bunch of parts. My meter is a good one and I couldn't find a voltage problem with it. So always keep in mind they may cause big problems! Thanks again!
 
Continuing with a new year and an old problem. I'm back in the water with the same hot start problem with the exception I purchased (yes this is the second new fuel pump from my parts office that supplies my Crusader parts. After months of research, I found only aftermarket pumps are available. Original supplier to Crusader which I understand was Carter hasn't made the two-inlet pump over 6 years which is still on my port engine (1996). So, started with using the port engine (which never had any problems) by switching each part from the starboard (problem engine) and then sea-trailing the boat, but each time problem remained on the starboard engine until we switched the fuel pump, now the port engine has the hot starting problem, and the starboard engine starts and idles perfect. Took off the new pump (second one) and purchased another (pump #3), sea-trailed and still starts but will not stay running. So, this has to be an issue with all these new aftermarket pumps. All suppliers show the Crusader part number as a reference which is 23234 and don't what to purchase another! Now to the BIG question, I want to install a Carter single inlet pump (Carter engineer gave me the part number) which has the correct pressure / GPH and run the TB return direct to the tank, (it did return to the two-inlet fuel pump as originally designed) What's your opinion or options! Thanks in advance for any help!
 
They must have had problems with that system. I have 1998 cruisers flybridge with twin crusader 454xli throttle body injection and my return lines go to the tank. I have heard that your style pump is hard to get and others have had to replumb the system. I think it would be better to have the return to the tank. I would bet your tank even has a fitting for it if not it wouldn't be to hard to rig up a fitting in the fill hose. I have seen several automotive efi add on systems do that.
 
Thanks, I wouldn't think a direct return to the tank would be a problem and yes, tank has a return fitting. Just knowing you have a system like that is very encouraging! I will do the retrofit this week and let you and the followers know how I make out.
 
Update, first yes, I have dual tanks and the returns are original to the tanks which checked out good. Thanks to everybody that gave me advise on my Crusader engine with the "would not idle (start) after running at normal temperature. To review, moved the second new fuel pump (two-inlet style) to the port engine and the start issue followed, therefore the issue is the pump, purchased another (this is the third)) "Crusader" pump (two-inlet style) from my local Crusader parts supplier as I have always done and installed it. After the sea trial as I've been doing all along, the problem was not corrected, and it would not stay running (Idling) and stalled as it has been doing since last August 2021. Cause was low to no fuel pressure again after it operated for a period time on all three pumps! Called Carter Engineering, they haven't made the two-inlet pump for 6-7 years, so it's not their pump, so I requested an alternative pump part number which was a normal single inlet pump to fit my Crusader TB's. The newer pump fitted into the original bracket; high pressure tubes fitted perfectly but had to revise the inlet line, from the filter to the new pump (no big deal!). Original TB return tube remained but at the end, I rerouted it to the original return to tank line. Engine started up perfectly, so out for a sea trail. It ran great, all through the RPM"S and it hasn't given me any trouble since the retrofit. Many trips out on the water and many normal restarts and idles! Put the engine on my laptop to check for "engine codes' All clear! I can say with confidence, it's finally fixed!!!!! My advice to anyone that has that two-inlet pump with a start or run problem, is to retrofit to the standard single inlet pump that is correct for your engine and if possible, use a Carter pump, not an "Unknown" Three of the pumps sold to me, failed after they ran for a period of time, but once cool, they worked! There was nothing wrong with my engines or installation and they cost me a lot on money, ton of time and as important, use of my boat! Let me know if anyone has any questions, glad to help! Again, thanks for all the help!
 
Yes, there will always be another! There's a new saying: on a boat something is always broke, we just don't know it yet! Carter part number is P5001 for pressures 20 PSI max.
 
15 inches of vacuum seems a little low to me.Check for vacuum leaks.If none are found try advancing the throttle slightly when it wont stay running and see if that helps.If it does check your tps setting and base idle.

Where is the best place to test for vacuum on these TBI engines?
 
I used the TB vacuum port for the MAP sensor. By adding a short piece of vacuum hose and a "Tee" to the port, you can put the TB hose to the "tee" and the hose to your vacuum gauge.
 
I used the TB vacuum port for the MAP sensor. By adding a short piece of vacuum hose and a "Tee" to the port, you can put the TB hose to the "tee" and the hose to your vacuum gauge.
I'm a new member and this is my first post. I hope you folks are still around, I have a 1968 Trojan 42 with new remanned twin Crusader 454XLi long blocks. The starboard engine just recently started shutting down at low idle after being on a 1-2 hour trip and then sitting for an hour or so. Starts up just fine then shuts down within 5 minutes. We have been focusing on the fuel pump, filters, vent lines. Mechanic found no or minimum (2-5 psi) fuel pressure. We now believe that vapor lock is part of the problem. We put in a new fuel pump, putting out 26-30 psi, but no fuel in the secondary filter. (I'll be honest, I don't know what the spec for fuel pressure is supposed to be. They seem to be all over the place on Crusader info.) This has happened consistently in the same manner for my last three trips. Mechanic doesn't understand why the return fuel goes into the fuel pump rather than the fuel tank or primary filter/water separator. Voila! You guys discovered the same thing. After searching the net till my eyes are crossed, I came across this thread. Our 2 plus your 2 equals 4, so I think we've solved the problem. I have several questions and hope that you can provide the answers: 1. Would the part number be on the pump? 2. What is the correct fuel pump pressure spec? 3. According to my info, that part number is 23234 in the XLi Parts Manual. Is this correct? 4. Can you provide me with a substitute part number for a single port fuel pump for the 454XLi TBI? 5. Is the Carter part number you gave (P5001) a current number or the old part that's no longer available? Thanks in advance .
 
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