Hot Intake Manifold

I am in the process of starting and breaking in my new 200. Seems to be running well (except that it dies whenever i turn off the choke. I am chalking this up to not fully broken in and not hot enough) It currently has a clifford header with no exhaust system yet installed.

Question:
After letting the motor run for several minutes the intake manifold seems to be getting pretty hot. I turn it off and a little smoke is seeping out of a crack at the junction between the carb and the manifold. (This indicates a vacuum leak which I know needs to be fixed...) But the hot manifold and the smoke I don't know what to make of. Is this normal?

If you're engine is dying because of new, its not right!!!!!! The only thing that really needs to wear in, is the rings, if they are too tight, then it was sized wrong.
FIRST guess from this side says vacume leak????????? Its hard guessing from this side, but getting rid of a few questions firstly can really help.
What is the dwell reading??????????
What do you mean by rebuilt motor, I assume it is from your statement??? breaking in???????? the smoke, depending on how serious it is?? could be as simple as oil or paint burning off??? Make sure any areas that could cause a vacume leak are checked firstly,,, is the bottom of the carb loose by itself??? bad or no gaskets,, what was done to the head????
vic

Running the engine with no exhaust attached can't be helping much.

Aside from the vacumn leak, if it is actually getting hot , double check your cooling system. I dam near cooked a fresh 383 dodge onetime because a mouse had decided to move into the top tank of the radiator during the engine rebuild.

This is a remanufactured engine from Hiperformer in spokane WA. Completely redone. I have to assume everything internally is correct including dwell time (at least until I eliminate some other possible causes). The rings are definitely tight. When I turn the engine off the engine stops pretty quick. But i believe this is normal for a new engine with high compression.

I used a new gasket when installing the carb. I will replace today to see its effect.

Another issue may be the PCV valve I installed. Through the earplugs I can hear a constant weezing like air being sucked trough a tight opening. Was coming from the area of the PCV valve. At low rpm (high vacuum at the carb) the PCV valve should be closed correct? I believe mine is not working correctly if this is the case.

Cooling system seems to be working correctly as the radiator and tubes get warm after a time.

Your help is much appreciated.

Hiperformer builds great enines. I doubt that the engine is the problem. Like Vic said correct any vacuum problems. You can always call Hiperformer and talk to their tech guys. Their engines have a great warrany.

I rather doubt any builder would have anything to do with setting the Dwell, I threw that at you as I wanted to see your response????? So, next question is,, what is it set at???? My point is, we need to take out all the little possibilities firstly, to avoid going in circles??? Please correct me if wrong, however, I was under the impression it will not stay running while idling???? The PVC valve needs to suck air at a controlled rate, and it must match you engine. If the Dwell is not correct, we are fighting a loosing battle from the get go??? the same as if a battery were good, however not charged. It sounds like your engine is fighting itself, with perhaps more than one issue at once. Dwell is the easiest thing to eliminate and get rid of,, next is fuel and the carb, all the time vacume also. A vacume leak, poor fuel and bad dwell and timing issues can make a motor run lean and overheat things like pistons and valves...trying to help someone over the net is hard also, as its always what does the person know or understand, what has he done that he has not mentioned, what has he done that is not right,,,,,,by choking the motor you could be forcing it to run instead of letting it run??? fuel could be as simple as the wrong gas cap and a plugged vent line, poor fuel pump, carb, etc,,,, I like to nail down the easy things firstly instead of all of them at once.
vic

replaced the gaskets at the carb and eliminated the vacuum leak.

The whine I heard before and attributed to the pcv has gone away.

Dwell is at 35 degrees at 550 rpms (idle) using a dwell meter.

Advance at 500 rpm's is at 6 bdtc (per the manual). Internet sources stated 12 degrees (sounds fishy since total advance should not exceed 15 degrees.

I let the motor run choked for longer than normal this evening and once choke was turned off it ran terrific. Purred right along. A combination of the fixed vacuum leak and me just not letting it warm up enough.

The intake manifold is still getting hot however. I realize the header is directly below it but it just seems to be hotter than it would get by just heat rising from the header past it.

A friend suggested that it might be a bubble in the cooling system that is not letting the coolant into the head therefore heating the intake manifold.....

Coolant is at the proper level in the radiator. The bottom radiator hose gets warm first then the top one.

I really appreciate the help here guys. I am definitely a newbie at this so question everything!

I suspected a vacume leak, but it could not have been as easily as it could be??? Its always the first step to get rid of any question marks that you can easily get out of the whole issue firstly, then pound your head in the wall,,,, LOL....
The idea of a PCV is for it to be taking both any blow by and any contaminates back into the combustion chambers and then burn it, so it has to be sucking all the time the engine is running. However at a metered amount for that engine.
As far as the intake goes, its attached still~~~~~ even if the headers come out the bottom, the exhaust ports are right there as part of the head. I use two methods for both checking the actual temp, but also, to see where that is exactly on my gauge?????? nice to know what your gauge is REALLY telling you,,,,, one is the cooking one, and put it in the radiator,,,or a digital one that I put in there also,,, I don't trust the lazer ones, as I have had different readings from them that didn't add up??? so I have a personal doubt about them. If yours is not reading hot, this way, its not then, and just normal, the intake is all cast iron and part of the cylinder head, with the exhaust ports there also. I used to see cracks there in the center two ports once in awhile, but yours sounds like its okay. Sounds like your thermostat is working,, however you haven't stated what temp one is in there??????? Check the temp out with the cooking thermometer,, and see whats up???
vic

I was going to check the temp as suggested and noticed two drips on the garage floor under the engine as it was warming up. I took a closer look and they are coolant. I hadn't messed with any coolant today. Must investigate source. Closer inspection reveals that along the entire left side of the head gasket there is a minuscule amount of coolant gathered there. After turning off the engine you can see small bubbles form and then pop quickly the entire length of the gasket.

Possible causes:
Head bolts not torqued properly = factory defect
This seems implausible. Unless that was something I was supposed to check before firing the engine. If it was it was not listed anywhere in the literature nor in the startup procedure.

Non flat interface= factory defect

Defective gasket = factory defect

Blown head gasket
I believe it is possible to have blown the gasket if the engine was detonating. However I have never driven the van, and I know it is timed correctly.

Options:
Re torque the bolts.

Pull the head and replace that gasket.

Do I have to replace all the fluids?

Is this serious enough to get the manufacturer involved?

Pretty frustrated right now. Any thoughts would be very appreciated.

What a total bummer and timing could have been anything else!!!! Sorry to hear it,,,,
First guestion hits me, is what is your compression rate???? you said the new high compression, which leaves me wondering if it has high compression or if you mean its new higher compression compared to old????????
If its a high compression, which now a days translates to anything over 9/1, I would suspect the head gasket is gone, but that also, isn't swallowing well either?
In the old days, on difficult sealing gaskets, we would spray on a film of copper coat, some simply used aluminum paint. It was rumored to seal the gasket surfaces better. I never had one come back so can't answer that one for sure????????
I would want to pull the head and visibly look at the gasket, the head surface, and the block surface. The gasket can be like reading a book sometimes,,
BUT I would call the re builders first, and ask them what they think. You have to try and cover your warranty with them if possible?? I guess it depends on which way this goes, as it could be a cheap gasket???? a bad block surface???? or head???? Mike speaks highly of them, so it sounds like they will back there product????
DEFINITELY,, check the torque readings,, come up on them slowly from 25lbs so that YOU know what they are torqued at. They can't fault you for that.
In order for you to have blown the gasket, you would have to have seriously overheated the motor,,, and from this end it doesn't sound that way at all? I would FOR SURE also, now record the temp readings and not by the gauges.
Have all of that ready when you talk to them.
Its uncorked, has not gone down the road with a load on the crankshaft, has only sat there idling,,,, it shouldn't have an coolant and or air bubbles coming out the side of the head,,,,,
Please keep posted on it,,, curious to follow and help if I can,,,, Hope you have a Merry Christmas besides the problems...
vic
vic

Been a while since I was able to get to the van...

Compression is just way higher than what i was used to on the old worn out 170.

I called hiperformer. They weren't too surprised. Told me to run the thing and it would seal up on its own.

So thats what I just did for the first time. Way more power than the 170.

Now I just have to learn how to drive this thing... Which I am going to start another thread on right now.

Just my thinking= 1= recheck dwell - set @ 28-31 degrees 2= set timing @ 8 advanced. tighten the dist . hold down so it wont move & re-check timing. let warm up- check in radiator9cap area) when warm - see if water(coolant) is flowing - also see if in water theer are a lot of bubbles?? If so - head is leaking - or-?? remebber - something is letting compression into the cooling system- due to burned gas is higher pressure than cooling system & will pressureize it with cap on & will heat the engine up & will eventually overflow - when cooling pressure overcomes the radiator cap pressure setting. I had one a few years back that i could drive 4-8 miles before overheating badly - finally discovered that I had 1 cyl with a crack in the bore- and had to pull the head & lower each piston to BDC and examine closely- almost couldnt see the crack - yet felt it with my fingernail!! Had to sleve the cyl. engine ran so good after that was done . Any eng builder can miss that one when building a motor. Good luck. PS: im in spokane & never herd of this builder.??

Spank wrote:Been a while since I was able to get to the van...

Compression is just way higher than what i was used to on the old worn out 170.

I called hiperformer. They weren't too surprised. Told me to run the thing and it would seal up on its own.

So thats what I just did for the first time. Way more power than the 170.

Now I just have to learn how to drive this thing... Which I am going to start another thread on right now.

Hmmm, when first got my Hiperformer I put Clifford headers on it and tried to run it without any exhaust and it ran like crap but ran well after putting the rest of the exhaust system on it.