exhaust temps
 

What would make the exhaust temps on one side of engine alot higher than the other side. So high in fact that the rubber exhaust hose was smoking.
This happened during break in procedure, all new parts in engine. Primed with oil. When first fired appered to have alittle valve train noise on the side in question. (port side, 1,3,5 and 7)
So far have checked timing, spark plugs, plug wires. Have engine builder coming thursday to listen to engine before removing. Any ideas?
thanks

Re: exhaust temps
 

If the exhaust hose was smoking, I would say you weren't getting enough water to that side.

Re: exhaust temps
 

When we rigged up for water, I removed belt from raw water pump, then removed the outlet hose from pump and attached a 1" water supply hose to this. I have water x-over so no circulating pump. When running appeared to have same amount of water coming out exhaust. Engine not running hot. Kept eye on temps of block, intake manifold etc. with infared heat gun. Have gil exhaust, all new gaskets. The side in question, riser was around 25 degres hotter than the other.

Re: exhaust temps
 

Dont worry about the few snags that youve got jus dont rush it. Take your time and work out the kinks. I rebuilt a 454 ho two years ago. all new parts from GM per. parts. get the motor in the boat after we primed the oil pump. start it up- no oil pressure- :eek: had to pull the motor back out and get another new oil pump. after that no problems. :drink: who built the motors for you over there in tickfaw?

Re: exhaust temps
 

Thanks for the understanding, and yes I guess I do need to be paitient. Don't get to work on boat much. Home 2 weeks out of month. Oilfield. I did not have engines built around tickfaw. Greg Porcello @ Porcello racing engines in Hattisburg Ms built them. Known him personally for 8 years. Have confidence in his ability just alittle aggrevated with it all. Hope someone on this forum can give some ideas as to what to look for.

Re: exhaust temps
 

ran water crossovers on a few boats and had same problem with hot spots checked them on the water and where worse under load temp differences of over 75 degrees on exhaust and even worse on heads from front to rear went back to circulating pumps end of problems.

Re: exhaust temps
 

Are you sure you dont have an airlock on that head? Sure sounds like its water/cooling related. Why no circ pump, you running a blower?

Re: exhaust temps
 

Need more info;

What gen are your blocks? Do you know what your oil temp is, not from a hand held IR sens but a guage? Do you have remote oil filters? If so you may be bypassing your oil coolers. What heads? Do you KNOW you have the right gaskets for the heads and block combo? If you had a rubber exhaust pipe smoking you have a much greater than 25 deg differential on the mills. Did you try backflushing the cooling? Does the temp go up at idle or under load? Fresh mills can run a little hot but it sounds like you may be getting hot enough to make the oil breakdown.

Re: exhaust temps
 

If you are running a crossover, are you running a thermostat? Do you have holes drilled in the thermostat. If you don't have the holes, on a fresh startup there will be a lot of air around the thermostat and it won't open until the engine gets really hot. Maybe its a lack of water. Trying to break in a cam on a hose may just take too much water.

Re: exhaust temps
 

Info on engine combo- '89 454 mark 4
bored 30 over
KB 9.2 to 1 pistons
square port heads
merc. alum. high rise intake
rebuilt and dialed in quadrajet for engine
combo by SMI
Gil super stock exhaust
x-overs with 165 degree stats. drilled
ultradiyne cam-@50 223/231, 280/288
110 degree lobe seperation
All new valve train, non roller cam
Harland sharp roller rockers
New push rods
All internals were replaced with new with the exception of crank and rods.
Did backflush coolers, high temp is only on port side of engine, do not have oil temp gauge, positive on right gaskets, did not idle, I shut down and have not cranked it back yet. If it is water related I don't understand why it also has noisy valve train on that side. Other engine smooth as silk. I do have remote oil filters. If that head is air locked how do I fix that?

Re: exhaust temps
 

That cam on a 110 lobe sep is a reversion risk. I run a flat 224, 232 on 114 and Im real close. If you have the cam card, post the rest of the numbers.

If your one head is air locked it would get hot real fast and cause the valves to stick in the guides or a host of other problems. You may need to run a water line from the water passage at the rear of the intake that is typically blocked off to the water passage at the front of the intake on each side. You will need to have it machine, drilled and tapped. I would put the circ pump back on first.

Re: exhaust temps
 

complete cam specs from cam card- duration @50-intake 223/exhaust 231
lobe lift-intake .3088/exh. .3233
lobe seperation 110
seat duration @ 006 intake 280/exh.288
gross valve lift intake.525/ exh.550
valve lash hot intake .000/ exh .000
degree intake lobe to 108 ATDC
seat timing int @.050 BTDC 5.5 ABDC 37.5
seat timing exh @.050 BBDC 49.5 ATDC 1.5
Alot of these numbers I really dont understand but I specificaly asked cam rep about reversion and this is what was recommended. I also belive I got the same cam specs off this forum. If I will have a reversion problem, what can I do other than replace brand new cams?

Re: exhaust temps
 

It depends on your risers. I have the real short low ones used for the silent choice call magnum choice. If you have the full height risers you might be ok.

Im not a cam expert by any means. It appears that even though your lobe seperation is closer, this cam is a lot faster (ramp) than mine. Do you have the timing numbers at .004 (SAE J604) or .006?

Re: exhaust temps
 

I doubt if the cam is going to cause any problems. It has less duration and less lift than the cam used in the 454-400hp Cyclone. The Cyclone used those old log style manifolds with a very small, short riser. It certanly isn't causing any overheating problems. I read on another thread that water flow in Merc engines is biased toward one exhaust manifold anyway. If there is a shortage of water, it's going to show up in the manifold that normally gets the least water.

Re: exhaust temps
 

Sounds like you don't have enough water pressure to "force" enough water through both exhausts to keep them cool. Without any water pump, the water travels the path of least resistance, which is not equal to each exhaust manifold. If you have a water pressure gauge, what was the pressure? I would look there before I started looking for "major" problems. Eliminate the "easy" possibilities first.

Re: exhaust temps
 

I agree. Always eliminate the simple things first.

Re: exhaust temps
 

You could try temporarily restricting (pinching off) the supply hose to the cooler side to see if the warmer side cools off. Might help you determine if it is just a flow issue.

Dave

Re: exhaust temps
 

First sorry it took me awhile to get back with anyone, been mardi gras on the river. Had to ride with someone though. On the cam specs that was all that was written on the card so dont know any more about it. I do have the tall risers on the exhaust and they also have these cone -like plates installed between the riser and manifold that I belive is supposed to help on reversion. Does not however have internal flappers. Previous owner removed them and installed slip in baffels and retained the rubber flappers on the outside.
Have thought alot on the high temps and feel that water flow has alot to do with it. Did not think about pinching off the line to other side to see if it made it cooler.
On the cam, was this a bad choice for a cam? What hp can I expect with this combo?
One other thing, It appears to have a lifter that does not want to pump up. First fired engine it started ticking then progressivly got worse, guess oil was getting hot making it worse. Called cam manufacture and explaned problem, suggested re-adjusting valves. Did this and helped some but still hear ticking. Said to pull them out and they would replace the set. All valve train new before starting engine. Would this cause black soot in the exhaust? After running for short period to trouble shoot noticed alot of soot on transom and outdrive where soot was mixing with water. Thanks for all of ya'll help.

Re: exhaust temps
 

I cant answer on the cam selection, its quite a bit different than mine but it looks like it has much less overlap even with the 110 seperation. Your duration at .006 is much less than mine. just a quess. If youve got the tall risers you are probably fine. The cone shaped things keep any condensation that develops on the walls of the pipes after you shut down from dripping down into the exhaust port.

DO NOT replace just the lifters. It will likely kill the cam. It been my experience and a lot of people agree that the cam and lifters have to be broken in as a set. Im very worried that the cam manufacturer would even suggest this.

The soot is probably carb setup, most likely overjetted. Needs to be setup properly at all speeds.

Re: exhaust temps
 

Oh, and if you dont know about cam breakin, make sure you follow the rules on that. It may be too late.

Proper breakin lube and Gm EOS in with a 30 wt dino oil.
NO Idling or cranking.
20-30 minutes at 2000-2500 rpm. Then avoid as much idling as possible for another half hr or so.
Change oil and stick with dino for a while.

I have run into a bad lifter on my last purchase. I caught it while setting them before I ever fired it so I got lucky.

Re: exhaust temps
 

hey formula,
well I have followed the cam breakin procedures to the letter from cam manufacture. As fate would have it it had a ticking noise right from startup. Never got better. Ran 30 min. Decided stuck lifter, tore it down to look and found that several lifters had metal particals on the end touching cam. Cam appeared to not have a consistant wear pattern on the lobes either. Called cam manufacture and they are going to replace cam and lifters. Have you heard of any of them helping on some of the labor costs also. This is getting old pulling engines. Getting way to intimate with this project.
By the way, used rotella 30 wt and 1 pint of eos oil additive. Fired right up and ran 2200-2600 rpms fo 30min. I'm at work now, offshore, check email every few days. thanks for any insight.

Re: exhaust temps
 

I will be sweating a new flat cam breakin real soon. All I can do is pray at this point. Labor, I doubt it, your lucky to get the parts.