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Can anyone tell me what the compression ratio is for my specific motor? Vin code is “H”
 

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Yo Dahak390,
Welcome to our site!
See attached page;
8.8:1
For posterity, only because I posted this in response to another member's PM;
For now, Member 1989BroncoMan wrote here, "
I just ran compression test on '89 Bronco with 5.8, first dry then wet (adding a small amount of oil to each cylinder before testing).
The numbers were (dry/wet):
5 - 65/65 | 1 - 70/70
6 - 60/60 | 2 - 65/65
7 - 60/70 | 3 - 50/55
8 - 60/65 | 4 - 60/60

I read in a Ford manual that, "The indicated compression pressures are considered within specification if the lowest reading cylinder is within 75 percent of the pressure recorded for the highest reading cylinder."
By this standard, number 3 is a touch low compared to number 1, but probably close enough to call it OK.
But it seems like overall the numbers are low.
Moreover, number 3 was a little more problematic than I put in the chart. On the dry testing, it first tested at 45 psi. Clearing the pressure from the gauge and cranking again put it at 55. I averaged the two to put 50 on the chart. Then, on the second, wet test, it first tested at less than 30 psi. I unscrewed the gauge from the spark plug hole, added a little more oil, and reinstalled the gauge. This time it went to about 59..."
Read more @ https://www.fullsizebronco.com/forum/7-1980-96-bronco-tech/181307-compression-testing-numbers-too-low.html
°
In 96, "Compression Gauge Check
Make sure oil in crankcase is of the correct viscosity and at proper level and battery (10655) is properly charged. Operate vehicle until engine (6007) is at normal operating temperature. Key off, then remove all spark plugs (12405).
Set throttle plates in wide-open position.
Install a compression gauge such as Rotunda Compression Tester 164-R0250 or equivalent in No. 1 cylinder spark plug opening.
Install an auxiliary starter switch in starting circuit. With key off, and using auxiliary starter switch, crank engine at least five compression strokes and record highest reading. Note the approximate number of compression strokes required to obtain the highest reading.
Repeat test on each cylinder, cranking the engine approximately the same number of compression strokes.

Test Results
The indicated compression pressures are considered within specification if the lowest reading cylinder is within 75 percent of the highest. Refer to the chart."
Compression Readings — Interpreting
It is recommended the Compression Pressure Limit Chart be used when checking cylinder compression so that the lowest reading number is 75 percent of the highest reading.
If one or more cylinders reads low, squirt approximately one 1.5 ml (1 tablespoon) of SAE 50 weight or equivalent engine oil on top of the pistons in the low reading cylinders. Repeat compression pressure check on these cylinders.
If compression improves considerably, piston rings are at fault.
If compression does not improve, valves are sticking or seating poorly.
If two adjacent cylinders indicate low compression pressures and squirting oil on pistons does not increase compression, cause may be a cylinder head gasket leak between cylinders. Engine oil and/or coolant in cylinders could result from this problem.
Example Readings
For example, check the compression pressures in all cylinders. If the highest reading obtained was 1351 kPa (196 psi) and the lowest pressure reading was 1069 kPa (155 psi), the engine is within specification and the compression is considered satisfactory.
□●□
Here is the 1989 EVTM, Emissions & Pre-Delivery Manuals, Partial via mrnewland1 in Google Drive @ https://drive.google.com/drive/mobile/folders/0Bz1eScc6s4raOHd0WlVnMUw4WjQ?usp=drive_web
Slow scrolling for me with lousy Comcast service.. Find page # of item desired in contents, then flip screen flip down like spinning a bearing (a no-no) then stopping periodically to see which page you're on.

1989 Bronco Dealer Brochure @ 1989 Ford Bronco

Free registration for some wiring diagrams (86 through 96) and Technical Service Bulletins, (80 through 96), same as by Ford @ BBB Industries- Premium Alternators, Starters, Power Steering Products | TSB's & Wiring Diagrams

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