Sudden Increase in Blow-by

[Lee_in_KC]

Do you have a pic of the intake gaskts ??
dave

No, but I'll get some for you in a little while.

 

[Lee_in_KC]

Here you go...

Is there any particular detail or close-up you want?

 

[2old2fast]

Well , I'd say wrong gaskets , reason being these have the exhaust port crossover , you need w/out , like a 1204-1205 [depending on port size] it appears that the crossovers were blowing exaust gas in to the valley.... also , I can't quite see how well they were sealing at the bottom of the ports.... when you re-install , it's good practice to put a LIGHT coat of silicone around the water ports... another fyi is felpro offers an S-3 suffix gasket [1205 S-3] they have a steel inner core to help prevent gasket slip/distortion...
be back in a couple hours
dave

 

[RPM]

Yea but the manifold has no heat crossover, so it does not go anywhere.

 

[EX JUNK]

I've been following this since returning from a short vacation and I must say that my hat's off to Lee for the way that he has stated his problem so that the engine pros on here were able to diagnose his problem and give him some well versed solutions. That is the way that this site should work. Great work guys!

Jim

 

[2old2fast]

Yea but the manifold has no heat crossover, so it does not go anywhere.

That's why I suggested that they vented into the valley, poor fit & no where to go..
dave

 

[2old2fast]

In the end , it's up to Lee , or someone who can physically touch & look at the gaskets , manifold & heads to make the determination as to what was leaking , this long distance diagnosis can only go so far ..
dave

 

[Lee_in_KC]

Here are the left and right sides of the intake manifold. Not very clear pix, but looking at them live it does not appear that oil was coming in through the bottom of the intake runners. The gasket was stuck pretty good in those areas. I can't say for sure whether exhaust was getting out from under the gasket into the valley... I wouldn't bet against it. By the way, if you can't tell, the manifold is upside down!!

I do appreciate all the input I'm getting. You guys have caused me re-think other things. to look at things I wouldn't have thought of and re-think other things.

On the intake-to-head gaskets, I wouldn't have been smart enough to pick those on my own. At the time I was building the motor I was posting a lot of questions and getting a lot of guidance over on Hotrodders.com. I'm guessing someone over there suggested those gasket

 

[GT63]

Lee, I've been following this thread with much interest. I've been collecting parts for a total rebuild of my T and hope to get started on it this fall. After a lot of research I decided to go with a DART SHP SBC short block that was assembled by Dart and is specifically designed for Street blowers. It is 406 CI , has a forged crank, rods and pistons, and is milled for copper head gaskets. I haven't started the build yet but it will be a full roller motor. I have to say the DART SHP block is a looker even unpainted.

 

[2old2fast]

How would "milling for copper head gaskets" be any different than any other head gasket ? Now milled for O-rings I understand , but what would be different for gaskets ?? just curious...
dave

 

[Lee_in_KC]

Yeah Grant, I saw that on the Dart website. A little spendy for a retired guy, but awful tempting! I'm still leaning in the direction of building the short block myself. The Dart SHP empty block is at the top of my list of possibilities. I guess what I need to do is make a list of the parts I need/want and see what it adds up to. Could be close to the cost of the built-up 406!!

 

[2old2fast]

Lee , was the intake manifold new ??
dave

 

[Lee_in_KC]

Lee , was the intake manifold new ??
dave

Yes. It was part of the blower kit I bought from BDS.

I mentioned this in passing earlier but now I'm thinking this was a significant contributing factor. The intake-to-head bolts were not properly torqued and several of the inside bolts were almost finger loose. The bolts that came with the BDS kit were socket head using a hex drive. I couldn't get to the bolts down in the pockets with the torque wrench with a normal hex drive and had to use a extended ball-head hex drive...

As you can see the drive is at an angle to axis of the bolt. I don't know exactly how this affects the torque reading, but I assume the actual torque at the bolt head would be a little less than what is indicated on the wrench. I torqued an extra 5 lbs. to compensate. Still, none of these bolts stayed torqued. Again, no thread sealer or Loctite was used on these bolts.

 

[Lee_in_KC]

Grant, where did you get your Dart 406?

 

[2old2fast]

So you're leaning towards oil coming from the bolts being sucked into the intake ports ??
dave

 

[Lee_in_KC]

So you're leaning towards oil coming from the bolts being sucked into the intake ports ??
dave

Yes, and exhaust heat and pressure getting into the valley through the poorly-sealed/improper gasket, and excessive blow-by due to poorly seated rings. Did I leave anything out?!?!?

 

[2old2fast]

I think the oil leak started it , excessive oil on the rings overheated the rings causing poor sealing , then the nail in the coffin was the exhaust crossovers blowing into the valley .. Hey , this is like CSI , only we could all be full of it
dave

 

[Screaming Metal]

Yes. It was part of the blower kit I bought from BDS.

I mentioned this in passing earlier but now I'm thinking this was a significant contributing factor. The intake-to-head bolts were not properly torqued and several of the inside bolts were almost finger loose. The bolts that came with the BDS kit were socket head using a hex drive. I couldn't get to the bolts down in the pockets with the torque wrench with a normal hex drive and had to use a extended ball-head hex drive...

As you can see the drive is at an angle to axis of the bolt. I don't know exactly how this affects the torque reading, but I assume the actual torque at the bolt head would be a little less than what is indicated on the wrench. I torqued an extra 5 lbs. to compensate. Still, none of these bolts stayed torqued. Again, no thread sealer or Loctite was used on these bolts.

When you have this situation, use a short bit driver, then a universal a extension, then your torque wrench. Also, the allenhead needs a washer under it. When you go together with it again, smooth the burrs down where the allen 'dug' in the first time.

Also, put sealer on those bolts. Torque down in 2 or 3 sequences. 1st pull to about 15, 2nd pull to 25, then finish it on the 3rd. This gives a chance for the gasket to crush and seal properly, lets the sealer on the threads spread up and down the threads and lets the bolt stretch, if its going to.
If your motor sits overnight before you put the blower on, retorque, you'll probably find a few thats a touch loose....

 

[Screaming Metal]

Hey Ron! I'm retired! I can't afford Big Al or Shafiroff, as much as I would love to have one of their motors!!! I'm leaning towards doing my own. I actually was planning on building my own the first time, but was running out of time to make the 2006 NTBA Nationals and took the shortcut of having the short block done for me. I was still working then and was building my T in the evenings and weekends. Now that I'm retired, I have the time to do it right.

I have most of the tools I need. The main things I still need are inside and outside gauges, ring grinder, ring compressor and a few other incidentals. I think my heads are good and I don't need to do anything with the springs. I do need to clean up the intake valves and runners, maybe replace the seals.

I'm going to watch the video I have on building a performance 383 to get motivated and also see if there any other tools or other gee-gaws I need. I am one of those folks who neither lends nor borrows tools. If I don't have it, I either buy it o or rent it.

Check out Goodsons.....

 

[Screaming Metal]

I like Jasper Engines, do not know if they do a 383. Could your pcv have pulled oil into the intake?

If oil was shooting directly at the open hose, thats the purpose for a baffle at the pcv hole in the covers....