I have a set of turbos that came off a car with 15K on a rebuilt motor and I was going to put them in place of my current stock units with 70K. Upon inspection I was thinking I should have the very small cracks in the manifold welded up and grind them back flat again.
For those who have actually done these repairs what did you use for the rod/wire material when you welded them up. I have access to a really good welder/ fabricator but I want to be sure he uses something proven when doing the job. the cracks are very small now and I thought I could get more life out of them if I fixed it now.
I have my trans out for a new ACT replacement kit and thought it would be a great time to swap the turbos out also until I saw the hairline crack between the primary and the gate valve wall. now I am thinking about going through the thing first. and replacing it at a later (winter) time.
How prevelent are these cracks and how soon will they return if I weld them up? the car gets a few 100Mph+ runs a week but is always cooled down properly afterwords and Mobile1 oil is changed at 3000 miles.

 

I'm in a similar situation, and I'm planning to drill through the crack tips with a small (.10") drill to slow down their growth.

Dave

 

I have had several sets done .I grind out the edge around the complete port and the cracks .Then any porting and all the reshaping is done . The welder must preheat the parts before welding with nickle rod or nicad rod .Then I grind the ports back to shape .The surfaces are then milled flat ,or cut on a surface grinder .The set BNR built for me had cracks.So I reshaped and ported the houseings and manifold .Had them welded and opened the wastgate to 1.38 inches .Made a bigger door yada yada .I have a set in storage that was done and ran for a long time untill an apex seal spit through .The cracks did not return on them .The sets done for my customers have not been looked at ,they are still running . The welder I was using has changed jobs but he may still be able to do the work ,I do need to check with him because I had a call this week for this job . I think the key to the best job is welding completely around each port,not just the cracks .

 

I am trying to keep this car healthy and pristine as a daily (summer) driver as I have a Porsche 911 Frankenstien project car that has been my works project for 10 years.
I want to get as much life out of these turbos as I can so I thought welding them up first would prolong their usable lifespan.
I tend to be that guy that starts out to change spark plugs and ends up rebuilding the engine (as long as I'm in here) so I am attempting to keep the FD on the road and as stock as I can except for reliablility mods.
I did Silicone hose job.
5th gear Syncro and upgraded pall
SS Downpipe.
I have a AMS ECU that I have had in and out 3 or 4 times but have never really got it to be a full fledged solution to all my driving conditions here in Wisconsin.
Now I am putting in an ACT SS clutch/PP/TOB/PB.
I got the Turbos at a good price so I thought I would swap them but now I may wait and do the welding/ shaping and install later.

 

I had a crack in the cast iron exhaust manifold of my Civic, and the weld repair lasted about 75 miles. What bites is that the 'header' on my Civic is integrated with the cat, and therefor is a $500 peice.

 

Sounds like the person that did your Civic manifold didn't prep it properly. You can weld on cast iron just as easily as any other metal. However, if you don't prep (preheat) and do it right (nickel rod), the repair will last for only a short period of time. If you have a 92-95 CX or an 88-91 CRX HF, those parts shouldn't be too difficult to get.

Sonny

 

Can't say for sure they did do it the right way. They did warn me to not count it lasting too long. I was hoping for a bit more then 75 miles though.