Testing the intake manifold of your Indian for leaks is easy to do and should be done as early on as possible! Believe me! Or not because you can do as you please!
The intake manifold on your Indian is like a boring uncle. He doesn’t look like much, and you may not think much of him either, but he will ruin your party without you even realizing it!
I had been warned!
At very early stage of the renovation project of my Indian, Minty 🙂 I was told that manifolds could cause numerous problems. It was recommended to me to test it for leaks. It is written in the original Indian manuel too. From what I had understood, years of service and potentially having been tighten again and again, could have cause significant damages and it could well be the culprit of many of the issues we had.
So yeah, I had been warned!
But being warned isn’t always enough…
Did I manage to do the test? Nope. Not until recently at least.
Was it checked during the rebuilt of the engine? No, not really. It all went too fast. It looked ok anyway. (and spoiler, maybe it was!)
So what happened?
Well I’m not sure how I finally managed to convince my dad. I think I just didn’t give him a choice really. One day, when we started the engine, it didn’t go so well…
The decisive moment
When my dad and I are working on the bike, we tend to split tasks. With his big and strong hands he does most the hard work, and when small and precise jobs are needed, I do.
When starting the engine, he usually is the one to kick, and I stay on the other side of the bike to control the carburetor.
One of tests of the engine, before my test drives actually, didn’t go so well. The engine was starting perfectly but was running unevenly. We tried and tried and then it popped and popped. We stopped, as we needed to figure out what was going on. Like with everything, it could have been a number of things: Electrical problems, carburetor adjustments, manifold… My dad is always fairly quick to consider that it must be the carburetor, because he never really recovered from the day I touched the needles. Needles he had never touched! So yeah, he is basically always blaming me!! That’s ok.
So we stopped, and I went to the other side of the bike, just looking at it and noticed my bran new exhaust pipe had turned yellow, at the level of the rear cylinder. I was distraught.
I know, I know, I can’t keep it looking like new for ever. And eventually it will turn yellow or blue or whatever. It is absolutely fine if it means that I rode Minty extensively. It isn’t fine if it is changing color, just by starting it in the driveway!
The actual reason I felt distraught and slightly ashamed, is that the recommendations to test the manifold for leaks, came back haunting me.
It seemed obvious to me that the rear cylinder had run too hot compare to the front one and that meant that there was likely a leak at the manifold level. This also meant it could have probably been avoided, if only we had done the test sooner.
So this was indeed the decisive moment and I said: we are testing the manifold for leaks.
Testing the manifold for leaks
So that was it, we were going to test the manifold and there was no going back.
Here is the most comprehensive article you can read on the topic: http://virtualindian.org/11techleaktest.html
With this in mind, I asked my dad to create a test plate. As you can see on the picture, he use a wood board and didn’t bother too much about the shape!
But it did the trick and that is what matters. He used regular nuts and bolts to tighten it to the manifold. One could add sealant to make it extra leak proof. We didn’t even need to do that.
I used the regulator that I got with my spray guns to reach the recommended 15psi or 1 bar of pressure.
And, well… suspicions were confirmed. Check out the video below.
There were indeed bubbles forming at the level of the manifold connection to the rear cylinder.
The good thing is that there was no bubbles at the level of the front cylinder. This was good for the obvious reasons that it meant that there was no leak there. But also good, because it showed the test works. If both cylinders had bubbles, my dad probably would have dismissed this as normal. Here he could clearly see the good and the bad! pfff…
Now, it was unclear if the bubbles were coming just at the bolt level or also at the dreaded level of the nipple.
We had not removed the nipple from the cylinder when redoing the engine and I got scared we might have damaged it, while sanding it or else.
Well, in any case, the test was conclusive and confirmed we had one more issue to handle… but how?!
Handeling our manifold leak
Well this isn’t a piece of cake. It certainly should be handled before putting the engine back on the frame. I was therefore slightly desperate. And by slightly, I mean terribly! I went back home, after that week end, happy we did the test but with absolutely no solution in sight. If the leak was at the level of the nipple, it was going to be a real nightmare.
I knew just one thing at that point: we needed a wrench which would allow us to screw or unscrew the manifold bolts, for a start. My dad said he didn’t have one, but clearly he had managed to remove the manifold previously, so he must have had something that worked. But… Well, I just bought a new one.
When I came back with it, I guess he understood I wasn’t going to let this go. He finally found an old wrench of the appropriate size which he ground it to fit the current disposition.
At first, he didn’t remove enough on the sides. He would put in place, try to screw the bold, argue that it was impossible and just be annoyed. I then showed him that the wrench couldn’t move because it was touching the cylinder! Not because the bolt was tight!
So he ground some more!
And the magic happened! The bolt was tighten just a tiny bit. Hooray!!
What my dad said was impossible, happened! Just for this, I was happy 😉 Yeah, on such matters, things get really tense sometimes!
Testing again
So the next day, we were going to do the leak test again. That did not happen before my dad created a new test plate, just because he wanted to use a different air compressor.
The test worked perfectly with the first compressor. But like so many other times, when something works, my dad has to spend hours coming up with a different method. However, when something doesn’t work (you can refer to the bushing massacre for a great example) he will keep on trying for hours.
This is absolutely insane to me! It drives me crazy. I left the garage and baked a pie! Time well spent if you ask me!
Now, I hear you thinking that doing the same thing over and over, expecting a different result, is the definition of stupidity. Yeah, well, the thing is that I truly believe my dad is still trying to create problems just so we still have something to do. That he’s worried I’ll leave with the bike and never return or something like that. Probably partially unconsciously…
Anyway, the test did not work with his second air compressor. There was just not enough air pressure. He kept on arguing that the air was leaking by the exhaust… We are not trying to blow the engine like a tire, dad! This isn’t the goal!
Please, let’s just use the other air compressor because we know it works!
And it worked and…. no leak!!! Real happiness here!!
Well, I know, that this might not last and that having tighten the bold, might have cause some further issues which will show up later. Because that is how it goes. Leak – tighten – bigger leak – tighten again – enormous leak and boom…
But then, maybe not!
If he managed to tighten it when it had been tighten by our mechanic who is much stronger, then maybe, with a bit of luck, it means it was just not tight enough. I want to believe!!
Only time will tell… But for now, this is it. No more manifold leak!
Important notes
1 – As mentioned in the excellent article linked previously and here again: http://virtualindian.org/11techleaktest.html, spraying gas around the manifold nuts is a bad idea and will most likely be inconclusive. This is what the Indian manual recommends actually, but just don’t do it!
Plus I would add, that it requires an excellent & trained ear to hear the reaction of the engine. And personally, I know I don’t have a trained ear!
2 – Handle this when your engine is off the frame. When we confirmed beyond a shadow of a doubt, we had a leak there, I was so afraid this was going to turn into a financial nightmare. Replacing the manifold is one thing that could work, but what if the nipples were damaged? Worst, what if the cylinder was damaged. Even if not, what if the new manifold and cones or else didn’t fit? We do not have the tools to handle. So I was already considering how to bring Minty to our mechanic and the cost of the whole thing stressed me out! Do it first!!
In conclusion
Once more, this topic became a highly contentious thing between my dad and I. By this time, if you have read any of the other piece I wrote, you know we don’t fight so much, but get really annoyed at one another, while mostly trying to hold it back. It is often tense between us and there are topics, I know in advance, that are going to be more difficult than others.
The manifold was one of these difficult topics. I don’t know why, but I knew it would be.
When the leak was confirmed, I was so pissed. As mentioned at the beginning, I had been warned this is a very common problem. I was pissed my dad didn’t agree to do the test when the engine was dismantled. It would have been so easy. And if there was a problem, we could have addressed it with the mechanic, who helped us with the engine. It would have been an additional cost, but not a terrible issue.
Confirming this, now that Minty is whole again, is a complete different story.
So yeah, I was so, so pissed…. Until I realized it was my fault. And I know this isn’t the first time I say it, but because it is the second time at least I realize it, I am mentioning it again: Early on the project, I wasn’t strong enough and confident enough, to just do this simple test. Just like I wasn’t strong enough before to require we do certain things, a certain way.
I know you know by now, that I started this renovation project with no mechanical knowledge. But this clearly had more consequences than I thought as it also meant that I wasn’t able to do the things, I knew we should be doing – like testing the manifold. And it could have had dire financial consequences too.
It just felt a bit weird to write this (again) and I suppose it is quite normal that I didn’t have neither the knowledge or confidence. Early on, I was eager to learn from my dad, my goal was not to challenge him, not even to question him. Things changed along the way and I think this is hard on him.
So the manifold issue got me from pissed to sad and I don’t know how to handle the rest!
