I have used this technique on many small engines, using clean 1/4" or smaller soft braided nylon line, including two strokes with wall ports, and large engines too. I have never had a problem getting hung up. Or a problem at all. It is good for chainsaw sprocket and clutch changes. In the field you can use the saw's starter cord while it is still on the saw, if you have no ther way.

Just make 100% sure the piston you are blocking has the valves all closed and not trying to open as the crank moves a bit. I would lock the flywheel or make a holding fixture if I could, before using rope. Normally getting the nut or bolt OFF is worse than on. The (factory defective)HB on my wife's Mercedes has a big allen that is about 400ft/lbs, I think. I have a new upgraded HB that has been sitting in the box for some time now. I'm going to have to weld up a holding fixture but am lazy. The one big bolt design is fast for the engine plant but a pain to work on.

The replacement engine I bought was rebuilt before I installed it. I did the rebuild work myself. I thought alot about how to get that nut back on to specs. I made my own counter hold tool using two long box end wreches, put a strong bolt through the end of the wrenches, with washers and nut, this attached them together, then bolted the the free ends into the balancer bolts to form a triangle. This was done after the engine was installed, used a jack stand to hold the wrenches from turning with the crank. Luckily a friend had a wrench to borrow. Worked like a charm.

Used the same set up but with two more bolts and nuts in the free ends to make a counter hold for the timing gears. Allowing the bolts to be longer to fit in the holes of the gears. Though for this the wrenches can be considerably smaller.

DanR 94 964 277,000 miles (44,000 on the new engine)
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DanR

Dear Robert,

Good p.m. I have no knowledge of B6xxx engines. I dislike the concept of introducing any foreign material into a cylinder. I would only do this, if there were literally no other way, to get the job done.

Before I got the counter-hold tool - which holds the crank pulley in place, while the crank bolt is loosened or tightened - I used a 1/4"-wide, straight tipped screwdriver, to lock the engine. The screwdrive tip - per the FAQs - should be inserted into the ring gear teeth, right next to the bell-housing's edge.

If not more than 1/2" of the screwdriver tip is inserted, it will not damage anything. The screwdriver should be positioned against the side of the bell-housing, such that when the crank bolt is turned, the slightest movement locks the screwdriver into place.

One does have to go under the car, and remove the aluminum (aluminium) brace, at the front of the oil pan (six hex nuts). If one lacks the counter-hold tool and cannot get under the car, then use of rope inside the cylinder, is the last resort.

A possible alternative might be to fill the cylinder with gasoline, and then replace the spark plug. This, too, should jam the piston. However, one will need a suction device to remove the gasoline. If an attempt is made to start the engine, while the cylinder is filled with gasoline, severe damage could be done, including breaking a con rod.

In short, if you don't have the counter-hold tool, go under the car and use the screw-driver. It is the least risky method.

Yours faithfully,

spook

I advocate the rope "method", having used it many times over some 25+ years. With valves closed at TDC, I see no way the rope is going to get jammed anywhere. Certainly not between the piston and cylinder wall. IMO, "legend" is the operative word.

BTW, I do now own and use the counterhold tool, convincing myself I needed it a few years ago. But for someone that has just 1 or 2 cars to maintain, I don't see the tool as a "must have" item.
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Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.