Leak down test help needed

[msargius]

I am trying to do a leak down test which I never did it before. I hooked up my hose to one of the spark plugs, all the air came out of the exhaust manifold ( I have the riser off). Then next spark plug, all the air camoe out of the carb. I was reading that I need to turn the engine over until the piston at top center... The problem is I don't know how to do it.
Some say cranck the engine, others say do it manually.. which one is right? If manually how to do it?

I will appreciate the help if possible with a photo or a scatch or even none...
Thanks everyone.

 

[bomar76]

Re: Leak down test help needed

1. Remove ALL spark plugs
2. Put your thumb over the spark plug hole
3. Rotate engine with tools by hand (bolt in crank pulley) CW untill you feel air rushing out of cylinder. You cannot do this with the starter.
4. Continue turning by hand until air stops.
5. That cylinder is now at TDC
6. Do leak down test
7. Write down results
8. Repeat 2-7 for each cylinder.
9. Reinstall spark plugs.
10 Reinstall plug wires.

 

[msargius]

Re: Leak down test help needed

1. Remove ALL spark plugs
2. Put your thumb over the spark plug hole
3. Rotate engine with tools by hand (bolt in crank pulley) CW untill you feel air rushing out of cylinder. You cannot do this with the starter.
4. Continue turning by hand until air stops.
5. That cylinder is now at TDC
6. Do leak down test
7. Write down results
8. Repeat 2-7 for each cylinder.
9. Reinstall spark plugs.
10 Reinstall plug wires.

Thanks bomar

But the problem is that I cannot get access to the crank pulley is its obstructed by the engine mount legs. Also there isn't a center bolt. According to manual I will have to support the engine from the front, remove mounting bracket. I will also need a tool that get attached to the pulley using three bolts so I can rotate it... Is there a simple solution to this...

 

[MexicoMike]

Re: Leak down test help needed

It's kind of a PIA, but you could get a helper, but drive in gear and turn the prop. Make sure allm plugs are out or you might not be able to turn it. Just my 2 cents. Good Luck.

 

[Bondo]

Re: Leak down test help needed

But the problem is that I cannot get access to the crank pulley is its obstructed by the engine mount legs. Also there isn't a center bolt. According to manual I will have to support the engine from the front, remove mounting bracket. I will also need a tool that get attached to the pulley using three bolts so I can rotate it... Is there a simple solution to this...

Ayuh,... With the sparkplugs out, tighten the belt,+ use the alternator pulley nut...

 

[msargius]

Re: Leak down test help needed

Ayuh,... With the sparkplugs out, tighten the belt,+ use the alternator pulley nut...

Ouch...I will try this one the belt it is quite worn, but I will try it...
For the belt to be changed the front of the engine must be lifted....discovered this today. (That will be my next problem)
thanks

 

[Bondo]

Re: Leak down test help needed

For the belt to be changed the front of the engine must be lifted....discovered this today. (That will be my next problem)

Nope it Don't,...
Just remove the 2 bolts on the portside, slip out the spacer block, change the belt,+ reassemble...

 

[zbnutcase]

Re: Leak down test help needed

And you are using a real leakdown tester, not just compressed air?

 

[bomar76]

Re: Leak down test help needed

Using something he cobbled together.

 

[Bt Doctur]

Re: Leak down test help needed

I`d say this sounds like the in-line 4 cyl. 120-140 Hp
Another way it to determineTDC is put #1 on TDC , remove the dist cap and look at the rotor tip.
Is it facing #1 wire and having the timing mark at "0" ,this is TDC of #1 piston. Now just follow the firing order and watch the tip of the rotor.The next wire is #3, then #4 and #2.
Test in that order and do yourself a favor and go to the Adults Section and download the manual for your engine.

 

[msargius]

Re: Leak down test help needed

download the manual for your engine.

I have the manual, you will notice that from my post....The problem manuals don't have the tricks that others know...You can buy and read a hundred manual....but experience is that what matters...
Thanks by the way for your trick....

 

[Bt Doctur]

Re: Leak down test help needed

The reason we say download the manuals is for YOU to have an understanding of what were trying to explain. You and I dont speak the same language so to speak.Most of our explanations are sort of "tech-speak "using the correct words.
Simple test "Define the spider or cross joint" .
We can post all of the answers you need but if you cant read the language ?????,
Think of the manual as the "translator"

 

[Bondo]

Re: Leak down test help needed

The reason we say download the manuals is for YOU to have an understanding of what were trying to explain. You and I dont speak the same language so to speak.Most of our explanations are sort of "tech-speak "using the correct words.
Simple test "Define the spider or cross joint" .
We can post all of the answers you need but if you cant read the language ?????,
Think of the manual as the "translator"

Amen Bro,... Amen...