breknraj

This may be a little optomistic, but with the melting that I have seen so far, I'm hoping that I will be able to get the truck to my working platform by the end of the month. Toward that end, these are the things that I am planning to do to get Worf back up and running to full capacity.

I'll have to do the things necessary to move the engine forward a few inches, so that I will be able to remove and repair the crossover. This picure is a crude illustration of what I have in mind for the repair. The crack is at the bottom of the junction between the pipes coming from each bank. I plan to re-weld the pipes, then grind the areas in red smooth so that I can add some diamond fishplates to the front, back, and bottom of the butt joint area.



I would appreciate any thoughts or ideas about this plan.

After I repair the crossover, I will replace the firewall insulation, speedo cable and the e-brake cable. All of these got fried from the exhaust leak. After I reposition the engine, I plan to fab a solid mount for the down tube to the bell housing, remove the forward cat, and replace it with a flex coupling. I plan to install the URD O2 sensor bypass. I figured that since I keep getting the rear O2 sensor code, anyway, dropping down to one cat and the bypass isn't that big a deal.

Anyway, this is what I have in mind, so feel free to fire away with whatever your thoughts are about it.

Elvota

I ended up with just one cat and the rear O2 bypass. To me, that's a good way to go since the rear O2 is only really monitoring the cat's performance.

That's an ORS crossover, correct? Maybe ORS would send you a revised version and you could return this one... or send this one back for repair?

I guess that would give you to much downtime.

breknraj

The down time isn't a huge issue (since I've basically been without it for the last few months), but I do want to get it back on the road reasonably expediantly once I dive into the project.

As far as I know, ORS would be happy to work with me on a repair, but I don't know about the fishplate idea. I might have to talk to Mike about it, and see what his opinion is. I know that it will give the crossover better structural integrity at that joint, and I don't think that double layers of steel should be an issue with temps and such. I just want to do whatever I can to avoid having to chase anything to do with the crossover for a long time to come.

Five1Nine8Eight

Same thing happened to my crossover, exact same places too! I pulled my whole engine and repaired them. It cracked last weekend so I think I'll just go to headers and a custom crossover.

If I keep the crossover, my idea was to install some flex after the collector and before the first cat. Like you said but I'm gonna keep my 1st cat. The hard mount to the trans is a good one.

My crossover has header wrap on it and that helped to keep exhaust leak damage to a minimum.

Post up pics of the Trans mount.

mt_goat

Raj, do you have a pic of the failure point. I'm thinking the main stess on it might be from the twisting of the engine on the mounts as it torques up. If that's correct, the brace from the bell housing might be the best idea. I guess you didn't have a flex coupling after the crossover before? If not, that should help a lot too. Even with headers you want flex couplings. Not sure about the extra fish plates It's an interesting idea. My gut feeling is the it will just push the weak link over to another spot. But that's just a guess, we need some FEA models run LOL.

I think I'm going to go ahead and install a brace from the bell housing on mine. I really don't want this to happen 1000 miles from home.

Here you go on the FEA models, just hire these guys http://www.sti-tech.com/sti/fea.php?...FQ-DIgoduGs5Uw

breknraj

Dale, I'm sure that the lack of a flex coupling and extra support on the down pipe were the major components leading to the failure. I will definitely address those issues, but as far as the fish plates are concerned, that is based on my previous knowledge and experience in welding. I can't make the slightest claim of being a great welder, but I do know that an unsupported butt weld is the weakest one out there. The fish plates should strengthen the joint, and in conjunction with the other modifications, I'm confident that it should allevieate further stuctural issues with the crossover.

The only thing that I'm not sure about is whether the double layers of steel at the fish plate might create hot spots or such that could lead to other problems, down the road. I'm just planning to use some plain steel exhaust tubing to make the plates, so I don't think that that relatively thin extra steel should be a thermal problem, but I'm not absolutely sure about that, either.

Anyway, this is the direction I plan to go, unless someone chimes in with any logical reason not to. I just wish that I didn't have to go through the other gyrations just to get to the stupid thing!

Red_Chili

Interesting. My crossover was the initial design of the ORS crossover, and when it failed, Mike put in the flex coupling. It has been flawless since. I did lose an exhaust gasket at the downtube, but if I had kept up on tightening the bolts... oh well, simple repair.

Some thoughts: I have a flex coupling about a foot behind the crossover, in front of the cat. I also have a FRORF crossmember that absolutely limits engine twisting on the mounts.

Either that has eliminated the problem or I just haven't run into it yet. Ask Mike though, he will at the very least be extremely interested in any issues out there. He stands behind his products with the best of them, and redesigns quickly if warranted.

mt_goat

Yeah Bill that should help a lot, I don't have the FRORF crossmenber but I have chained my motor mounts down to help limit movement.

ORS

We have 3.4L Performance mounts that helps with that twisting while still providing a decent daily driver (not too much engine vibrations transmitted).

mt_goat

Holy motor mounts batman! Yeah that should do it too Mike.

breknraj

Day---yum, Mike! Those are some seriously beefy motor mounts!

I'll have to do without, for now, though - I have a wedding to pay for, soon!

breknraj

The weather and the job finally aligned to get a little work done!

I have stripped the front of the engine, and discovered that my original 3.0 fan (the ducted style) has a crack on the inner hub plastic. Since I do not want to see it fly apart and cause the associated mayhem that I have read about from time to time, I'm wondering what some of you have done to use the 3.4 fan. I did a test fit, and I can see that I would have to trim the shroud to be able to run it. How does that affect the cooling, if at all?

I'm sure that I could get a new ducted fan from Toyota (and I know that that fits), but I'm also sure that it would be seriously expensive.

I am also thinking that I may revise my exhaust idea. My current set up is crossover pipe, down tube to turn, O2 sensor 1, cat 1 (under factory heat sheild), pipe, cat 2 (under second heat sheild), O2 sensor 2, then the rest of the pipe and muffler. My new thought is that I will still add a support from the bell housing to the exhaust, but I'm thinking about putting the flex coupling in between the cats. I would like to do this, so that I can retain both cats (and keep them under the heat shields). It would still suspend some more weight than just piping before the flex coupling, but I think that the bell housing support can handle most of that (in addition to my planned upgrade of the crossover weld joint).

Anyone with thoughts about these issues, please chime in!

Elvota

I still have the 3.0 fan, but will upgrade to a 3.4 style once I find one.

Regardless, I do not run any shroud now and have no cooling problems. This is also with a winch and TJM bumper up front, as well as the 100 plus degree days of the Scottsdale, AZ area.

So, my guess is Colorado would be no issue even without the shroud.

breknraj

Thanks, Elvota! That is very good to hear.

mt_goat

What are your temps running with that setup?

Elvota

I only have the OEM gauge, which I realize is not that precise. But...

...the gauge always sits under half and stays rock solid. Whether climbing big hills at free way speed or crawling the rocks. I have a radiator from Performance here in Phoenix. Bought it for the 3.0 and have kept it after the swap. Perhaps that's the key?

I know you had a lot of overheating issues Mt Goat with the same bumper setup, so I was waiting for similar after my swap. I have been happy with the results so far.

mt_goat

That's what mine does too. If I was to just go by my OEM gauge I've never had a cooling problem either.

Do you have the OBDII plug? You could get accurate temp measurement there.

Elvota

Yes... I should run around with the laptop plugged in to get some more accurate numbers. I guess I'd be more concerned if the needle fluctuated at times.

Ignorance may be bliss.

mt_goat

Here's what I came up with, I'll see if it holds up. I may have to check the bolts every now and then:

breknraj

No pix, since I'm at work, now.

After a summer of getting married, honeymooning, and trying to land a new job, I've finally gotten back to my poor truck in the last couple of weeks!

Did a partial engine extraction to get to the cross over, and pulled it off last week. I removed the header wrap, and found hat the cracked weld went halfway around the circumference of the joint!

I replaced the heat damaged cables yesterday, and will be crossing my fingers that I don't have to replace the speedo gear in the transfer case. I also replaced the melted heat blanket on the firewall with one that I picked up at YotaYard.

Today I picked up some scrap metal, including some exhaust pipe, and set about repairing and re-inforcing the crossover pipe. Someday, I am going to have to get the stuff I need to make my Lincoln a true mig - flux core works, but it's seldom pretty!

I took my time welding up tiny sections at a time to fill and repair the crack. Then I cut some sections of the scrap exhaust pipe to make three fishplates to bridge the joint on the front, back, and bottom. I also cut a small triangle of 1/8" steel strap to make a small gusset for the top of the joint.

All of this is probably over kill, but my hope is that I won't have to worry about it for a long time to come. I'll start modifying the exhaust support after I get the engine back in place (I'm hoping sometime this weekend).