1997 Crusader 454: Need component locations for compression testing

[Greg_E]

I am looking at a '97 Stamas 290 with single 454 throttle body injected Crusader. The engine is a Jasper remanufactured engine with about 50 hours on it. The engine has not been started in about 18 months. As part of my due diligence I drained the oil, did the prelube procedure using an external pump, and removed the plugs to spray some fogging fluid into the cylinders. The oil seemed to be very black for an engine with so few hours on it, so I sent out a sample to be tested. When I pulled the plugs they seemed to be dirtier than I would expect. Black oily residue on the insulator and a couple had carbonized bits stuck between the insulator metal body of the plug, and some light rust. The engine was not fogged when it was put up. at the end of the 2016 season.

I am familiar with the procedure to do the compression test but I am not at all familiar with Crusader 454's. I plan to use a remote starter switch to crank the engine. This will allow me to crank the engine without energizing the ignition system. Correct?

I watched a Mercruiser video where the mechanic connected it to a slave solenoid located on top of the engine but I don't know where that is located on this engine or if it even uses one. Where is the best place to connect the remote starter switch on this Crusader engine?

Also, Does this engine have an electric fuel pump or mechanical pump?

With the ignition switch off, the electric fuel pump would be disabled but it wouldn't hurt to know where the fuel pump fuse is located. Is it in the box with the circuit breakers on top of the engine?

If it has a mechanical fuel pump what is the best way to prevent the TB from injecting fuel into the intake manifold when cranking the engine? There are fuel shutoffs but I don't want to damage the diaphragm when it's trying to pull fuel through the closed lines.

Sorry for all the questions and thanks in advance for any replies. Also, I would appreciate any input as to the condition of the oil and spark plugs. This engine was a warranty replacement for the previously replaced reman. engine.

 

[alldodge]

I am looking at a '97 Stamas 290 with single 454 throttle body injected Crusader. The engine is a Jasper remanufactured engine with about 50 hours on it. The engine has not been started in about 18 months. As part of my due diligence I drained the oil, did the prelube procedure using an external pump, and removed the plugs to spray some fogging fluid into the cylinders. The oil seemed to be very black for an engine with so few hours on it, so I sent out a sample to be tested. When I pulled the plugs they seemed to be dirtier than I would expect. Black oily residue on the insulator and a couple had carbonized bits stuck between the insulator metal body of the plug, and some light rust. The engine was not fogged when it was put up. at the end of the 2016 season.

Not real sure but if a motor only had 50 hours, then this would not happen unless it was abused. My first guess is the motor has way more then that and its burning oil. If it is a new motor then I would contact Jasper with you findings

I am familiar with the procedure to do the compression test but I am not at all familiar with Crusader 454's. I plan to use a remote starter switch to crank the engine. This will allow me to crank the engine without energizing the ignition system. Correct?

I watched a Mercruiser video where the mechanic connected it to a slave solenoid located on top of the engine but I don't know where that is located on this engine or if it even uses one. Where is the best place to connect the remote starter switch on this Crusader engine?

There is a slave and its on top the motor near the ECM, and could be done the same why OR

Looking at the rear of the starter, connect one lead to the main post with the battery cable on it, put the other lead to the small post on the right

Also, Does this engine have an electric fuel pump or mechanical pump?

Being a 97 and fuel injected, yes it would have an electric high pressure pump

With the ignition switch off, the electric fuel pump would be disabled but it wouldn't hurt to know where the fuel pump fuse is located. Is it in the box with the circuit breakers on top of the engine?

The fuses (3 of them) are next to the ECM and a thin cover would need to be removed to gain access. Don't think you should need to both with them

If it has a mechanical fuel pump what is the best way to prevent the TB from injecting fuel into the intake manifold when cranking the engine? There are fuel shutoffs but I don't want to damage the diaphragm when it's trying to pull fuel through the closed lines.

All fuel injected motors will not turn the injectors on when the throttle is more then 3/4 open. You also want the throttle at WOT when doing a compression test, so this should not be an issue

 

[Greg_E]

Thank you for the reply. Everything I needed to know. The engine was installed under warranty in 2014 prior to the current owner purchasing the boat. I've seen the paperwork from the Jasper installer. The previous engine failed the oil analysis. Unfortunately I think the warranty is for 2 years so that has expired even though the boat has not been used.
I'll report back with the compression results early next week. Oil test results should be back late next week.

 

[Greg_E]

One other thing, It is pretty much impossible to pull the plugs and do a compression test when the engine is hot. How much, if any, are the compression readings affected if the test is done on a cold motor?

 

[alldodge]

Doing it cold is good enough to get some readings. If they are way out of normal then may need to try something else

 

[Greg_E]

With what I have described regarding the condition of the oil and plugs should I even bother to proceed with a compression test? The owner wants to proceed with the sea trial and do a compression test IF there is a problem with the sea trial. I don't see the point of incurring additional expenses involved if it has been determined that there is some problem of a serious nature. The compression test is just a first step in diagnosing the cause of the fouled plugs and black oil. The owner doesn't even want to do the preliminary step.

You have serviced on many of these engines. How would you proceed?


If we do a compression test, what readings should I expect to see on a cold engine?

What readings should I expect to see on a warm engine?

 

[alldodge]

Having a run is good, but may not show a weak cylinder. This may only show up with full load of folks and beverages. If the owner doesn't want to do the test then there may be an issue.

Cold or hot and new motor should read 150 psi. If done cold and there is a low cylinder out of 10% range of another, the test should be done again for that cylinder to see if it comes up. If all or most are low, then checking cold and hot would be better. In your case this should not be an issue with a low hour motor normally

 

[Greg_E]

AllDodge, Thank you for that information. You have been very helpful. I consulted with the mechanic at my marina and he confirmed exactly what you said.
As it turns out we will not be doing the compression test. the owner sent me a Mercruiser document on compression testing. I tried to explain that the 100PSI spec. mentioned and 30% difference between cylinders were the absolute minimum specs for a used engine needing a rebuild, not an engine just past the break in period. I also told him that because we had sprayed fogging oil in the cylinders to lube them prior to starting the engine, the readings taken on the cold engine could mask a problem with the rings. (engine has not ben started in approx 18 months) I suggested that we do the test cold and if we had low compression we would stop there because the engine has issues. If the readings were good we would need to run the engine to burn off the oil in the cylinders, in order to get an accurate assessment of the condition of the rings. He became belligerent and refused to run the engine. Needless to say, I won't be buying this boat.
To anyone looking at a boat in RI matching the description in post 1: Buyer Beware

I don't know if it is stupidity, dishonesty or both.
I always like this quote: You can't argue with stupidity. They bring you down to there level and beat you with experience."

 

[Lou C]

Well he seems to be hiding something that you found evidence of!