Logo
FULL SITE MENU

Flushing or cleaning out risers/elbows on a 454 crusader

C

contender31

Regular Contributor
I have a 1990 Tiara Open with 2 454 crusader 330 hp. I have 1 riser that reads 200 degrees with a infra red gun and three that read 150-155, i believe the one that reads higher is clogged somehow. I took out the inspection or cleaning threaded plug on the top of the elbow and it appeared rusted. Is there any way of flushing or cleaning them out through this or any other area. Note the temperature on the manifold side of the elbows reads 151 but on the exhaust side it reads 200.

thanks any words of wisdom would be greatly appreciated
 
If they are only a couple years old, they may benefit from an acid bath. If they are much older, a replacement is in order, especially if the boat has been in your area since delivery. Recommended practice is to change both on an engine. Experience indicates the other side won't be too far behind.
 
Correction --- it is the exhaust elbow that I am getting the higher temp reading, the riser is at 151. What does this tell you?
 
'Fraid not. You might be able to improve things by removing only the risers and poking them out in the rear with a rod rotated in an electric drill. Some risers (elbows) have small slots where crud can plug.

Jeff
 
Thanks I just bought the boat and have no idea when the riser or elbows were last replaced. I guess I could pull off the elbow and riser to inspect to see if that is the problem. I thought there may be an easier way of testing these before taking out the wrenches? What if I wer to take off the hose that feeds the raw wtaer to the riser and push water through it. Would that gives me an idea if it was clogged? I could test each side to see if they are equal in water pressure. Will that work beng that I have the inspection plug out of the top of the elbow. I can inspect the water flow through these holes couldnt I?
 
Having the plug out won't help at all. The critical port is the one that the water shoots thru where the hose connects. I'd suspect one or more of the holes is clogged with "iron flakes".

If the risers are in the raw water loop, like DD said, change them with the elbows. If you don't know how old they are, it will be much cheaper to replace them all, now. less aggrevation, stress, etc.

as far as the diagram goes, a serial number would help. From your numbers, a fresh water cooling system install is likely, verification of its use helps, too.
 
Yes the risers are in the loop of the raw water as stated, do you suggest doing both risers and elbows on that engine only? The cost for material is $ 500 fpr each engine.
thanks for your input
 
That sounds like the going rate for the parts.

I'd change both sides on the problem engine. You can do only the hot riser/elbow if you wish but the other side won't be far behind. It will be a lot of repetitive effort when it clogs. And you can bet the risers/elbows on the other engines won't be too far behind.

Don't forget to get the coolant out of the manifolds before disassembly and you will need to purge the coolant side after reassembly. Several recent threads have the details....just use the Search function for Elbows on the Crusader section.
 
FYI: I had replaced the ENTIRE manifold/elbow cooling system on both engines within the last 4 seasons and two weeks ago I noticed a slight rise in the port engine (the slightly older fix)temperature. I changed both elbows knowing this was going to start chain reaction of events that will EVENTUALLY overheat. Presto! Back to normal....never moved higher than 160 all last weekend. Those elbows were only 3 yrs and 9 months old.
 
Thanks for all your help --note: I am fresh water cooled so draining the anti freeze shouldnt be necessary as there is a plate that separates the coolant from the raw water but thanks for the heads up. I noticed this morning that the riers are osco brand and the elbows are barr. I bet whoever changhed these last only changed the risers as Tiara uses barr exclusively from the factory. THis morning i stuck a hose into the raw water feed on both sides to the riser and the water ran through without any problems and identical. any thoughts?
 
Since the last part of the exhaust system can not be fresh water cooled, that would be where a blockage could be. A blockage here, where the raw water finally enters the exhaust stream, causes the other side--with more water flow--to run cooler.

Jeff
 
makomark said:
Having the plug out won't help at all. The critical port is the one that the water shoots thru where the hose connects. I'd suspect one or more of the holes is clogged with "iron flakes".

If the risers are in the raw water loop, like DD said, change them with the elbows. If you don't know how old they are, it will be much cheaper to replace them all, now. less aggrevation, stress, etc.

as far as the diagram goes, a serial number would help. From your numbers, a fresh water cooling system install is likely, verification of its use helps, too.
Click to expand...


Just for ****s and giggles I doconnected all 4 hoses that went to the risers from the heat exchanger and when I ran water through them witht a garden hose they all flowed freely and at the same pace. Does that tell you anything? Thanks
 
fastjeff said:
Since the last part of the exhaust system can not be fresh water cooled, that would be where a blockage could be. A blockage here, where the raw water finally enters the exhaust stream, causes the other side--with more water flow--to run cooler.

Jeff
Click to expand...


Just for ****s and giggles I doconnected all 4 hoses that went to the risers from the heat exchanger and when I ran water through them witht a garden hose they all flowed freely and at the same pace. Does that tell you anything? Thanks
 
It may be best if you call Tiara and order the manual for the boat. I have a 33 Open, which are rare and I got the last manual they had for $29.00. Then, I would go to the manual of this web site and order a Crusader manaul, you will need your engine seriel numbers which are near the flywheel. I paid $72 for my Crusader manual and it was a good purchase, almost forgot, I had to come back and order the parts manual from this web site and forgot how much that was.

BTW: I did not know Tiara used Barr, my manifolds and risers are Crusader. The replacement risers are also Crusader and were done 3 years ago by the previous owner.
 
Id say that within the 20 years of this boats life...someone had changed some parts somewhere along the line
 
Last edited:
Tiara doesn't alter the engine OEM's configuration, they design to it. Crusader has its exhuast components 'built to their spec' and when Thermo Electron owned the brand name, that spec included the crusader part number being visible on the castings. I doubt PCM has changed much....
 
That's a great test idea with that hose! Gotta remember that.

A suggestion: Put an in-line valve in the side that runs cool, forcing more water to the other side (the 'hot' side). A dumb fix, but it should work. No idea why it's doing that, unless the inside of the hose is delaminated or something.

Jeff
 
Back
Top