New heads are here!

[Donziweasel]

My new heads came this morning. Now I have to send them out to have them machined for the dual valve springs and lift. I am really excited to finally have this boat ready to run. If I can get them back by Wed or Thursday, will probably work on it non-stop until done or my rib gives out.

One question I have been wondering, how much power was lost on the wrong heads. I think the boat has 60 mph+ in it. Hopefully will be able to test some Turbo props on it this weekend if I can get it running.

[Donziweasel]

Scott, the heads were sold by Summitt as "vortec heads". It was partly my fault as I did not know that they were "summitt heads" not GM. The part I feel is there problem is that they do not specify these are DART heads. The main problem is that the ports do not match up. Buizilla caught this as he had just installed a set for you and saw the port difference. I am happy he had just done yours, and remember the port specs. Problems are as follows-

1. Ports are not matching very well in intake. The ports have a semi-circle cut at the top, for MPI. Hence the DART head I guess.
2. The heads wer crappy to begin with, they do not match up with any gaskets very well, incuding fel-pro and GM.
3. Due to the fact that they don't match, I had exhaust on the intake ports. The gasket that fits between the rails between exhaust and intake ports was actually over the edge of the port. The intake and exhaust were sharing ports.
4. The intake gaskets that did not fit also did not seal right on these heads creating port sharing and "crimped gaskets in places. Not only did this create port sharing, but also vacuum leaks.

Summitt Heads-
http://store.summitracing.com/partdetail.asp?autofilter=1&part=SUM%2D151124&N=700+309822+115&autoview=sku

GM heads (which were actually cheaper)-
http://store.summitracing.com/partdetail.asp?autofilter=1&part=NAL%2D12558060&N=700+305337+4294840140+115&autoview=sku


Thank goodness for Buizilla and high res cameras. When I posted the pics, he immediatly pointed out many problems with these heads and gaskets fitting. Once again, Donzi.net saved me much frustration and possibly an engine. Now just got to put her back together and get one of your Turbo's on it. :)

Here is a link to both heads, GM and Summit. Click enlarge and look at the ports and you will see the first problem pretty clearly. Summitt heads are junk, BTW.

[Carl C]

I just re-read the original thread all the way through. That's really something! Maybe your compression will go up too. Now you'll have to redo your carb though. http://www.donzi.net/forums/showthread.php?t=49859

[BUIZILLA]

couple things.... actually fuzzy installed his own heads, I was in charge of throwing wrenches across the room... :) chasing missing rocker balls and adjusting valves with a matchbook cover...

do you have self aligning rockers?? I forgot... read the instructions on this...

watch that 7* lock deal, some aftermarket retainers/locks are 10*, if you are using your 7*retainers and 7* with your new springs AND locks your good, i'm assuming the heads came assembled?? I still like the single behive springs better though...

I still think the exhaust residue in 4 intake ports is valve adjustment related... those 4 ports happen to be on the same plane in the intake for some reason too...

[Donziweasel]

The rockers are self aligning. Buizilla, you offered to walk me through valve adjustment. I hope this offer is still valid because I want to make sure I have it right before I hit the lake.

It sounds like Poodle's heads were more like a full contact sport than mechanics:bonk::)

Did he not lable and save all his parts? Did you manage to hit him with a wrench? Was he prepared with the match book or did he make you bring this high tech tool? I think I set a set of points with a match book once. Ah, I can't say anthing too bad, he did send me some kick ass props to try and said he would give me a ride in his critter one day.:wink::wink::wink:

[Carl C]

I think I set a set of points with a match book onceI Used to do it all the time. It takes 2 thicknesses of a matchbook cover.:convertib:

[Donziweasel]

Damn, I wish both of you lived out here. I would be most happy to crack a cold one, sit back, and spectate with a little management. I could tell you how good your torqueing of the heads is and tell Buiz how great his valve adjustment is.:bonk::) Oh well, hopefully it will go back together nice and not give me any trouble. I did cheat and ordered the heads through the company. Free parts work as well as ones you pay for!:):):)

[BUIZILLA]

:boat: :cool:

[gold-n-rod]

So, I sit in the bilge with a 24" ratchet, drink beer and bar the engine over.. Life is good :) :)

Any day with a Donzi is a good day (even when being towed back to port in the "haul of shame.") Life is good and life with a Donzi is better. As previously said, "If you are fortunate enough to own a Donzi, you are fortunate enough!"

[Donziweasel]

Here Here :beer:, truer words have rarely been spoken!

[mrfixxall]

The intake and exhaust were sharing ports.

Inpossible,,Dw you had your valves too tight like we talked about way long ago...:wink:

[Donziweasel]

I guess possibly a little air could have exchanged. The problem was the gasket on the rails between the ports was off, and actually on one set, off the edge of the port. Buiz is right, valves were probably off. My bad as I did not explain it very well. In the original post, you can see it with the high res pics I took.

http://www.donzi.net/forums/showthread.php?t=49859

[mrfixxall]

Intake valves on cyl # 6 & or 8 were to tight,,thats where the popping and the carbon came from..im not boubting buiz butits almost inpossible to get a vacume leak with those type of gasgets..they have little plastic doll pins that keep the gasgetas in place so they wont slide around and i dont really see a problem with those gasgets sucking air because their covering all the ports..

im rootsy and get the specs on what needs to be done with the heads so their on the money this time..

good luck!:beer:

P.s. vortech heads are designed to rob intake volume of air from other ports, thats why theirs not a rubber seal between the intake ports. so ive been told!

[BUIZILLA]

let's play blow up the pic and find the vacuum leak... :wink:

I did... :lookaroun:

[mrfixxall]

let's play blow up the pic and find the vacuum leak... :wink:
I did... :lookaroun:
Buiz if their was a vacume leak the engine would have sucked the rubber out of the gasget:yes::wink:
poor guy all he had to do was replace the intake gasgets and readjust the rockers...
best of luck john....

[98shovel]

i want to know how we see carbon on an intake port plus the little clean taddle tail,why hasnt any one said anything about that left open valley just waiting for something to fall in to the pan dw please put something in the valley before a screw or socket falls to the bottom then out comes the motor unless your a good fishermen

[BUIZILLA]

Buiz if their was a vacume leak the engine would have sucked the rubber out of the gasget:yes::wink:
poor guy all he had to do was replace the intake gasgets and readjust the rockers...
best of luck john.... so far, he hasn't found a gasket to fit those heads, the ports are cast shifted in one direction on both heads, even the intake bolt holes are not centered correctly in the gaskets.. pure crap..

that's my story, and i'm sticking by it..

[Donziweasel]

Thanks Buiz. No matter what gasket I used, they just did not fit. One of the pics in that thread is of a new Fel-pro on the Summitt head, still didn't fit. I could try 50 more gaskets or just go for the other heads. I get a discount through the company with GM, so I just spent 270.00 each for new heads.

Plus, the ports are still wrong , even though they might work. Those heads are for a MPI engine, hence the semi circles on top of each port. They were just not a good fit, so I was already half way in, don't have to pay for the heads, and why not? I want the boat right as I will probably sell it in the next year for an 18. Or keep it and get an 18 as well, hell, I don't know.

Lastly, Buiz did find a leak and a pretty good one. Like he said, blow up the pic of the Starboard ports and see if you can find it. Buiz already won a 6 pack for that one.

Buiz, I never did ask you if you thought I was on the right track by replacing the heads. Update, they should be back from the machine shop Thursday and me and the machinist decided to go with different springs.

98, I was very careful with the disassembly and the only reason it was not protected is for the pics. Currently, the hatch is on the engine and the engine is coverd in wrap. I have a nice shop for this kind of tear down.

[mrfixxall]

Lastly, Buiz did find a leak and a pretty good one. Like he said, blow up the pic of the Starboard ports and see if you can find it. Buiz already won a 6 pack for that

As i mentioned,,i have fixed many intake gasgets over the last 25 yrs and every one that had a vacume leak has sucked either the rubber or the paper materal away from that spot..Plus you mentioned it was popping through the carb which is usually a bad cam or the intake valves are to tight(which you should check your cam now to).....With the spark plug you showed which was fat would have been white or silver if it was leaking and last if that cylinder had a vacume leak and for as hard as you ran the engine it would have for sure pounded the valves out of the head from running lein...:wink:

good luck DW

[Rootsy]

I donno... my bet is on the vacuum leak... I believe I asked that question of Jon a loooooooooooong time ago... but anywho... :crossfing:

[98shovel]

from what i could see in the pic it looked like it had an intake leak swapping heads is the way to go so u can use a more common gasket
lay some shop rags in the valley carefull is not good enough take the xtra step things do go oops! ive been doing this for a long time all day and always take the xtra step

[Donziweasel]

I guess I will show where Buiz and Rootsy (he was typing in the leak when Buiz posted it first) found the leak. I know these pics take a while to load, but they are high res to show the details. Take a look at the first two ports from left to right. Look at the gasket under the first port. You can see where it is crimped and did not seal. That is at least one leak. It is a hard leak to find without taking off the intake.
Roosty, you are right, you did mention that first a looooong time ago. I used methods that were not exactly perfect to try and find a leak (brake cleaner around the edges of the carb and manifold). Still would have been hard to find in my opinion. In that pic alone, you can see the gasket does not fit.
The second pic of the grey gasket is the GM gasket. Both the GM and Fel-Pro were recommended by Sumitt for thier heads. You can see it does not fit either. Either both gaskets are defective (very unlikely to impossible) or the head is junk. I think we know Buiz's take on the heads and I agree. In any event, the new heads will be going in.
To recap, and I am learning alot from all of you in this, the boat was popping back through the carb and "bogging" on the low end off the line. The carb is set up for stock with the accelerator pump shooters up 1. A stock carb and pump shooters up one should and did create a rich condition at my altitude as we can see by the plugs, BUT this is the setting where the boat runs the best. It seems, from input from the boards, that the most common problem associated with this is a intake leak AND valves are too tight. Not only that, the heads are poor fitting and not quality heads. My problems are-
1. Bad heads designed for MPI that somehow are junk and do not fit the engine or intake which is designed to accept a standard GM Vortec head.
2. Intake leak under 1st port.
3. Ill fitting gaskets that possibly created other leaks and possible bad seals BETWEEN ports.
4. Valves too tight for this application.
5. Due to intake leak, boat running rich to compensate for lack of fuel flow due to low manifolf psi off the line.
Does this sound right? Buiz, Rootsy, Mike?
98, thank you for the advice on keeping the engine safe from contamination and possible debri in the intake. I layed some shop rags over the cellephane for added protection. Will be sure to clean and inspect before reassembly.
Now, are you sure none of you wouldn't like to visit Jackson Hole and help me put this thing back together? :wink:

[Donziweasel]

Ooops, the pic of the head with the leak didn't post, here it is-

Crap, won't post, try going back to the original thread, wonder what is wrong?

[RickSE]

...wonder what is wrong?

You can't attach a photo that's already been attached in another thread, unless you change it a little. Sometimes I just resize it a little, rename and it'll work.

Now that you got everything apart port match those suckers.

Do you mean the ports on the right (cyl. #1 & #3) where the center seal strip is not in the center between the ports, way over towards the #1 intake port?

Good old China crap probably. But hey they're cheaper right? Sounds like you found out they're not. I'm at the point now where I don't care if it's cheaper, I'll pay more for good quality parts.

[98shovel]

i love skiing jackson hole have never been their during the summer u by the round trip ticket and ill put it back together for u and spend and xtra day helping tune

[Donziweasel]

Pasted and cut on leak, take a look.

[Donziweasel]

Here is the big pic, leak circled in blue

[98shovel]

what no bite on the round trip

[Donziweasel]

Can you be here by Thursday?:):):)

[98shovel]

what thursday ha ha ha
do u have a time frame whene u want it done it would only take about 3 or 4 hrs to put back together then out to the lake we go

[98shovel]

dw check your pm

[Donziweasel]

got it, will call if I get in a pickle, might be able to pick up heads today!:)

[RickSE]

I don't know man that seal on the left looks good to me, seems to be plenty of metal under the gasket for a good seal. I'd be more suspect of the seal on the right.

How do all the plugs look on this side of the engine? I think if you had a leak one or more plugs would show it. Plug reading can be tough though since my old 350 would always run rich on cylinders #5 & #7.

Maybe I missed something but how did these heads get on the motor? I just assumed you were still running the stock GM heads after switching the intake stuff.

[BUIZILLA]

the pic in post 29 is not the real problem area, it's the other head that's not pictured.... none the less, the overall situation was unacceptable, and DW is correcting the problem forthright.

[Donziweasel]

Rick, I must admit I put the heads on last Aug. Just the wrong heads. I know they are junk when my machine shop told me unless I wanted them back he was going to throw them away.

[Donziweasel]

Ooops, wrong pics, now you should be able to see it, Buiz was right.

[kd5cue]

Ooops, wrong pics, now you should be able to see it, Buiz was right.was valves burnt on old heads

[Donziweasel]

The reason for the heads was not burnt valves, but the type of head. Old heads were non-vortec. At my altitude, the gereral consensus was that Vortecs would help my engine "breathe" better. Stock, my 16 went 47 mph at 7000 ft. Now, even with the bad summit heads, it runs 56 with more on the way.

[BigGrizzly]

All I can say is we are going to have one happy wife when it is done, Donziweasel's!!! I can hear it now " now John what are you going to complain about now?":wink::wink:

[Donziweasel]

That I don't have an 18c!!!!!:):):):):bonk::bonk::bonk:

Actually, I haven't complained too much. Been kinda fun and I have learned alot. Don't get me wrong, it has been frustrating at time. Not sure what life will be like when I am done, bliss perhaps?