Heads 454

[northern]

Each engine has 1750 hours. Each engine consumes 1/2 quart of oil every 100 hours. Is there any way to tell the condition of the heads? Should I be getting them rebuilt? There is no water in the oil.

 

[johngus]

a cylinder leakdown test would give you an idea of valve leakage.At 1750 hours though I would be worried about a valve breaking.I may also be worried though about putting new heads on an old engine.Sometimes after a tight top end you may end up with a lower end problem shortly after.I would think i would leave them alone unless I was taking alot of long trips.With the age of your engines and hours I would probably go through the whole engines .remember that old phrase about opening up pandoras box.

 

[expressboy]

Each engine has 1750 hours. Each engine consumes 1/2 quart of oil every 100 hours. Is there any way to tell the condition of the heads? Should I be getting them rebuilt? There is no water in the oil.

Think of it this way.... in a truck.. pulling hills with a load at 45mph that would equate to 1/2 qt in 4500 miles!
Leave it alone and run it...
EXPRESSBOY

 

[carterchapman]

Each engine has 1750 hours. Each engine consumes 1/2 quart of oil every 100 hours.

What a great testimony to the GM "Big Block". 1750 hours in a 19,000# boat! I can remember having 454's in a '69 Corvette and a '73 Caprice wagon - they could "pass anything except a gas station".

Northern - could you tell us how long (hours) you've owned your boat, any special maintenance items that you've done, etc? Or did you get this many hours with normal, scheduled service? How many hours per year, long cruises, or long idles, etc? Have you done regular oil sampling?

Thanks.

 

[fc3]

A half quart for every 100 hours is within spec for a new 454. Leave it alone unless you know that you have a problem. A compression check is a decent indicator of overall health. Also, if the boat's fuel consumption is about the same as always, then most likely the engines are fine. Sick engines don't perform well, and bad performance means bad fuel economy.

Best regards,
Frank

 

[northern]

Information as requested:
Purchased boat in 2006 with 650 hours on each engine.
2006 and 2007 put on 125 each year
2008 and 2009 put on 300 hours each year
2010 put on 150 hours.
All hours are from memory do not have log book with me.
Use SAE 40 oil with and no slick 50 or other liquids, just oil.
Change transmission oil once a year. It has always looked good
Changed plugs, distributor cap and rotor in 2009. Plugs looked good. Rotor and distibutor cap were worn. Engines always started well but after changing plugs, distributor cap and rotor they start instantly. Have not replaced ignition wires. Will do that this year.
Run boat at 1200 to 2000 RPM. Not too often we run it at 3600RPM for a couple of hours to get out of a storm area.
Engines blow a little white smoke when starting for a minute and will blow lots at 3600 RPM. The white smoke starts at 2500RPM and gets more as RPM go up.
Had heat exchangers rebuilt in 2009 they did not leak but were in need of it said the rad shop. The risers were clened at the same time they were 50% blocked but not pitted.
One raw water pump had the seal leak so replaced the pump.
One starter bendex teeth brock so had the starter rebuilt. Rebuilt starter turned engine over 50% faster so had other starter rebuilt. Think it was at 1400 hours.
Use regular gas and each engine uses the same amouth of fuel.
Hope this helps
Any advice I should do to the engines would be appreciated.

 

[carterchapman]

I would go down into the bilge and give them both a hug and a kiss, they've treated you well and deserve it. I also agree with the others, unless they start to act up, don't change a thing.

+1 Scott.

Northern,

Here's my suggestions:
1. Go to http://www.blackstone-labs.com/ and order their oil sample kits and sample your engine oils prior to your next change. I think they charge $25 per sample to run them.

2. On your next plug change, run compression checks.

3. Your smoke on start up (could it be light blue instead of white?) may be worn valve guides, or as simple as worn rubber valve guide seals.

4. I don't know your exhaust system layout, but steam may be normal from your exhausts when running under a load.

Or as Scott says - give 'em a big hug and love 'em a little more each year and don't worry about my suggestions.

I don't want to steal your thread, but I think you have the highest time big block engines that I've seen mentioned on the Forum. Thanks for telling us how you treat them.

 

[Jimmy Buoy]

I agree with the "leave'm be" crowd. A good friend and fellow boater has a 1990 35' Express with original 454's (straight shafts). Purchased new, he tooka 6yr trip from home to the Carribean and as far South as Venezuela. Current hours are over 3000 and they run like a charm. All original, just the tranny's were replaced since one was starting to make noise and he didn't want to take a chance. Lot's of 1200 RPM putting though.

Your's are just nicely broken in!!

 

[northern]

Did a compression check at 1,000 hours on the starboard engine and all were the same. Do not remember what it was.
Smoke is definatly white.
Exhaust system runs into a water muffler then out the side just before the stern on the sides at the water line.
Will send away for oil analysis kit and post results but it will not be untill July or August.

 

[Carver370]

As long as you keep them maintained as you are you will be fine. I have a good feeling the smoke you speak of is most likely steam. I have 720 hours on mine and I am the original owner, they still run like the day of delivery.

I have a close friend with a 33 Amberjack that has around 2900 on 454 Mercs, the only thing thats every been done is impellers, oil changes, and tune ups. Other than that hes put fuel in it and went. Oil samples show no abnormal wear and compression checks mimic what a 400 hour boat would according to our local mechanic. When you get a good one, you get a GREAT one or in this case 2 GREAT ones.

If the engines run fine, leave it alone. For how you say you run the boat the heads will be the fine for a long, long time.

 

[Jimmy Buoy]

White smoke is quite common on straight shaft setups. It's steam and has something to do with the long length of exhaust tubing to the thru-hulls. It usually is more pronounced when operating in colder waters, but humidity also is a factor.

My boat has been doing this for years. The Sea Ray brochure even shows it running on plane with two steam trails - and that's a new boat!

I think you're alright despite the "white smoke".

 

[Leafy Isle]

I think the biggest factor in engine life is the prop loading. Just like a diesel, prop the boat to turn rated plus at least 200 rpm, then run it at "normal" 3000 -3200 and the BMEP is down where it should be. In other words {for the aviators out there} don't run it oversquare. I have around 1500 hours on my gen 4 454's and they burn about a liter in 100 hours. Have always used Merc 15w40. I run them about 50% at cruise and 50% at 1400 rpm. Boat weighs around 20000lbs and I get 18 to 20 knts at 3000 rpm...

oh and to the original question, leave them alone!

cheers